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HANDBOOKGENERAL ENGINEERING

ABRASION RESISTINGHEAT RESISTING

CORROSION RESISTING

MARK OF QUALITY

MEEHANITE METAL HANDBOOK 9/19/05 12:38 PM

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MEEHANITE METAL HANDBOOKRevised 2005

Copyright ©2001 by Meehanite Metal Corporation.Printed in the United States of America.All rights in this CD are reserved.

No part of this CD booklet may be used or reproduced in any manner whatsoever without written permission.

For information, write to:Meehanite Metal Corporation10936 N. Port Washington Rd. #141Mequon, WI 53092 Phone 800-423-0992E-mail [email protected]

The trade marks MEEHANITEMETAL

M [DUCTLIRON] [ALMANITE]METAL

and [MEEHANITE] are registered with theU.S. Patent Office and designate productsmade under the direction and in accordance with the prescribed standards ofMeehanite Worldwide.

ACKNOWLEDGEMENTSMeehanite Metal Corp. gratefully extendssincerest thanks to all Meehanite foundriesfor permission to reproduce their photographs in this Handbook ofMeehanite Metal.

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The Meehanite Metal Corporation has been in business for overseventy years, developing a family of high performance cast ductileand flake irons described in the following sections. This handbook

of Meehanite Metals has been prepared fordesigners, engineers and purchasing executiveswho strive to improve product performance andreduce manufacturing costs. It presents themechanical & physical properties of each type of Meehanite Metal in a clear and concise manner in order to aid in the selection of the

particular type of Meehanite® which will most completely meet thebuyer’s requirements.

Meehanite Metals furnish industry with engineering materials ofknown and consistent properties on which casting design can besafely based. They have proved their value the world over from notonly the viewpoint of dependable service, but economy as well.

The following pages outline some of the advantages to be gainedby the use of Meehanite® and explain why this versatile material isso widely recognized and used throughout industry.

To compliment the development of these materials, Meehanitelicenses only qualified foundries to produce these products. Everylicensee is required to undergo a strict training regimen before theyare permitted to produce any grade of Meehanite. Further to this,an ongoing program of auditing is followed, to ensure that the stan-dards required for production are maintained.

If you are interested in obtaining a Meehanite license, you canfind out what is involved and the services we provide by going topage 88 - The Meehanite Connection.

PREFACE

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CONTENTS

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The Meehanite Process

General Engineering Meehanite Metal 14Nodular GraphiteType SF 60 (SF 400) High ductility, shock resistance 15Type SP 80 (SP 600) High strength and toughness 16Type SH 100 (SH 700) Superior hardenability, high strength 17Type SH 100 (SH 800) Heat treated SH type metal – a good

(Heat Treated) combination of hardness, strength andtoughness 18

Type AQS High endurance strength and air hardening 20Flake GraphiteType GM 60 (GM 400) High compression and tensile strength 23Type GA 50 (GA 350) High strength and density 24Type GC 40 (GC 275) All purpose metal, good strength and density 25Type GE 30 (GE 200) Good machinability and damping capacity 26Type GF 20 (GF 150) Exceptional machinability 27Type AQ Machinable “as-cast”, air hardens 28

Abrasion Resisting Meehanite Metal (Almanite) 31Type W Exceptional hardness, moderate shock

resistance 31Type WS High hardness, strength, toughness 32Type WSH High impact strength 33

Heat Resisting Meehanite Metal 34Type HS Maximum resistance to scaling 41Type HSV High mechanical heat strength 42Type HR Scale and creep resistance 43Type HE Thermal shock resistance 44

Corrosion Resisting Meehanite Metal 46Type CC Moderately corrosion resisting 48Type CR Resistance to corrosion and erosion 49Type CRS High strength and corrosion resistance 50Type CHS Recommended for use in acidic conditions 51

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Austempered Ductile Iron 52K300 High Impact with Good Strength 54K400 54K500 Exceptional Strength and Hardness 54

Engineering Data 56Effect of Section Thickness 56Thermal Conductivity 58Thermal Expansion 60Specific Heat 63Sub-zero Impact Properties 65Damping Capacity 68Dimensional Stability 71Magnetic Properties 71Machinability and Machining 74Machining Practice and Tool Design 74Speed Feed Relationship 76Preparation and Sharpening of Tools 76Machining Allowances 77Rolling Friction Galling and Seizing 78Galling, Seizing and Pickup 79Heat Treatment Data 82Temper Brittleness 84Stress Relieving 86Surface Hardening 87Coatings, Welding 87


Meehanite® pump impeller and casing.6


INTRODUCTION

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The Meehanite ProcessMeehanite Metal castings coverany casting within the overall castiron composition range that havebeen produced by the Meehaniteprocess.

This process involves a numberof patented procedures seeking tocontrol and produce the desiredgraphite distribution and thedesired matrix structure in thecasting. It depends primarily onthe establishment of a melt ofdesired degree of undercoolingoften referred to as constitutionand the controlled nucleation ofthis melt, usually by means ofalkaline earth silicide additions. It requires very careful selection ofraw materials, meticulous processcontrols and a very thoroughknowledge of the foundrybehavior of cast iron.

The Meehanite process involvesthe use of standard procedures inall phases of casting manufactureincluding gating and riseringtechniques, sand control testingmethods and many specializedmolding procedures. It seeks toeliminate guesswork, therebyresulting in an engineering prod-uct of high integrity and reliability.

Meehanite Metal TypesWhile the Meehanite process is aclosely integrated procedure andwill produce a truly qualitycasting, it is necessary for theengineer to have at his disposalexact figures on the physical andmechanical properties ofMeehanite Metal so that he maydesign with confidence.

For this reason, MeehaniteMetal has conveniently beendivided into a number of broadtype classifications each with itstypical properties which enablesthe engineer to select that type ofmetal most suited to his particularapplication.

On the basis of use, the follow-ing broad categories apply:1. General Engineering Prefix G2. Wear Resisting Prefix W3. Heat Resisting Prefix H4. Corrosion Resisting Prefix C

These categories relate to theend use of the casting and arefurther sub-divided on the basis of metallurgical structure andproperty values.


INTRODUCTION

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BASE UNITUNITS & SYMBOLS FORMULA

QUANTITY SI ENGLISH SI ENGLISH

LENGTH meter, mcentimeter, cm foot, ft

milimeter, mm inch, in

MASS kilogram, kg pound, lbgram, gm

TIME hour, hrminute, min same as metricsecond, sec

TEMPERATURE Centigrade, °C Fahrenheit, °F

CONVERSION FACTORS FOR PHYSICAL QUANTITIES

QUANTITY ENGLISH UNIT TO SI UNIT SI UNIT TO ENGLISH UNIT

LENGTH 1 in 25.4 mm 1 mm 39.37 x 10-3 in1 ft 304.8 mm 1 mm 3.28 x 10-3 ft

MASS 1 lb 0.454 kg 1 kg 2.20 lb1 lb 453.6 gm 1 gm 2.20 x 10-3 lb

TEMPERATURE °F 5/9 (°F-32) °C 9/5°C + 32▲▲°F 5/9▲▲°C ▲▲°C 9/5▲▲°F

AREA 1 in2 645.2 mm2 1 mm2 1.55 x 10-3 in2

ENERGY 1 BTU 252 cal 1 cal 3.97 x 10-3 BTU

FORCE 1 lbf 4.45 newton 1 newton, N 0.225 lbf

MACHININGFeed 1 in/rev 2.54 cm/rev 1 cm/rev 0.394 in/revSpeed 1 s.f.m. 0.31 m/min 1 m/min 3.3 s.f.m.

PRESSURE 1 psi 6.895 x 10-3 1 N/mm2 145 psiN/mm2

IMPACT STRENGTH 1 ft lbf 1.36 N.m 1 N.m 0.737 ft lbf

WORK 1 ft lbf 1.36 N.m 1 N.m 0.737 ft lbf

SPECIFIC HEAT 1 BTU/lb/°F 0.309 cal/gm/°C 1 cal/gm/°C 3.24 BTU/lb/°F

THERMAL 1 BTU/hr/ft2/ 0.34 x 10-3 cal/ 1 cal/sec/ 2.94 x 103 BTU/CONDUCTIVITY (°F/in) sec/cm2/(°C/cm) cm2/(°C/cm) hr/ft2/(°F/in)

Meehanite UnitsThis revised issue of the“Handbook of Meehanite Metal”has adopted the metric systemalong with the English system.The adoption of the metric system(International System of Units, orabbreviated as SI in all language)is due to the fact that the metric

system will sooner or later beuniversal and we already havehad many requests for metric data.

It would appear necessary topresent the relations betweenmetric measures of length, area,mass and derived units, andEnglish units.


INTRODUCTION

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DERIVED UNITUNITS & SYMBOLS FORMULA

QUANTITY SI ENGLISH SI ENGLISHAREA sq. centimeter cm2 in2

sq. millimeter sq. inch mm2

ENDURANCE newton per pound-force perLIMIT sq. millimeter sq. inch (psi) N/mm2 lbf/in2 (psi)

ENERGY Joule British thermal N.m ft lbfunit, BTU

FORCE newton, N pound-force, lbf kg. cm/sec2 lb ft/sec2

IMPACT STRENGTH newton-meter foot-pound-force N.m ft lbfMACHINING

Feed centimeter inch perper revolution revolution cm/rev in/rev

Speed surface meter surface footper minute per minute, s.f.m. m/min ft/mins.m. min

MODULES OF ELASTICITYtension newton per pound-force per

sq. millimeter, E sq. inch, E N/mm2 psitorsion N* N* N/mm2 psi

PRESSURE newton per pound-force per N/mm2 psisq. millimeter sq. inch, psi

STRESS newton per pound-force per N/mm2 psisq. millimeter sq. inch, psi

SPECIFIC HEAT calorie per gram– BTU per pound cal/gm/°C BTU/lb/°FCelsius Fahrenheit

THERMAL CONDUCTIVITY thermal flux(calorie per thermal fluxsecond) per sq. (BTU per hour)centimeter– per sq. foot– cal/sec/cm2 BTU/hr/ft2/

(Celsius per (Fahrenheit per (°C/cm) (°F/n)

centimeter), inch), K valueK value

WORK newton-meter foot-pound-force N.m ft lbf

*The possible confusion with this meaning of the symbol N and the newton N if not clear from the context must be avoided by the use of “torsion modulus of elasticity” instead of N.


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Each type of Meehanite Metal is made to a predetermined structure therebyassuring uniform and dependable properties to precise engineering specifications. Four typical examples are shown below.

MEEHANITE TYPE GM 60 (GM 400)Tensile Strength 60,000 psi

(400N/mm2)BHN (normal) 230

MEEHANITE TYPE AQTensile StrengthHeat Treated 65,000 psi

(448N/mm2)BHN Up to 550

MEEHANITE TYPE SH 100 (SH 700)Tensile Strength 90/170,000 psi

(620/1172N/mm2)BHN 263/600

MEEHANITE TYPE WSTensile Strength 60/80,000 psi

(414/552N/mm2)BHN 400/525


INTRODUCTION

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General Engineering TypesThis Meehanite Metal series isclassified into flake graphitemetals designated by the prefix Gand nodular graphite metalsdesignated by the prefix S.

The G, or flake graphite, metalsare subdivided according to thetensile strength because this is themost convenient method. Thismethod of division is used eventhough the engineer may be moreinterested in specific propertiesother than tensile strength.

Tensile strength is given inminimum values, but it should berealized that Meehanite Metal Gmay be produced to any specificminimum value either exactlycorresponding to any specific typeor to values that may fall exactlyin between designated types.

In short, all properties show agradual transition from thehighest tensile value to the lowesttensile value and are separatedinto various types only for thepurpose of specification.

Since we use the metric systemalong with the English system inthis edition of the Handbook, theMeehanite Metal series hasaccordingly adopted numericalsymbols for the metric designa-tion. This designation includesonly the Meehanite Flake GraphiteG Types and Nodular Graphite S Types.

The Meehanite Wear ResistingTypes, Heat Resisting Types andCorrosion Resisting Types remainthe same as the previous designa-tions because they do not involvethe numerical symbols.

Sub-divisions are:Flake Graphite “G” Types

Type GM 60 (GM 400)–flake graphite, sorbo pearliticmatrix or tempered martensiteif heat treated.

Type GA 50 (GA 350)–flake graphite, pearlitic matrix.

Type GC 40 (GC 275)–flake graphite, pearlitic matrix.

Type GE 30 (GE 200)–flake graphite, pearlitic matrix.

Type GF 20 (GF 150)–flake graphite, ferritic/pearliticmatrix.

Type AQ–flake graphite, pearlitic/bainitic matrix.

The relationship betweentensile strength (forming the basisof classification) and otherpertinent properties are given inthe appropriate section of thisHandbook.

The sub-numerals 60, 50, 40,etc., indicate the PSI units onequivalent standard test bars foreach type and 400, 350, 300, etc.,indicate the minimum tensilestrength in N/mm2 units.

For example:GM 60 (GM 400) means typeGM metal has approximatetensile strength 60,000 psi or400 N/mm2.


INTRODUCTION

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Nodular Graphite “S” Types(Ductliron®).Sub-division in this series again isfor specification convenience.Specific property values of anyvalue within the ranges given mayalso be provided.

Relationship between tensilestrength and other properties maybe found in the engineering datasection of the Handbook.Type SF 60 (SF 400)

–nodular graphite, ferriticmatrix.

Type SP 80 (SP 600)–nodular graphite, pearlitic/ferritic matrix.

Type SH 100 (SH 700)–nodular graphite, pearliticmatrix, or tempered martensiteif heat treated.

Type AQS–nodular graphite, pearlitic/bainitic, martensite matrix.

Wear Resisting Types(Almanite®).This series produced primarily forwear resistance while havingspecific mechanical properties isbroadly classified according tometallurgical structures which, inturn, determines the wearresistance.

These metals may contain freecarbon as graphite or as carbidesor both. Those containing carbidesas the major properties of freecarbon are white irons.

Subdivisions are:Type W 1

–carbidic, pearlitic matrix.Type W 2

–carbidic, martensitic matrix.Type W 4

–carbidic, austenitic matrix.Type WS

–nodular graphite, martensiticmatrix.

Type WSH–nodular graphite, austeniticmatrix.

Rubber cutting discs cast in Meehanite nodular iron.

Meehanite crankshafts.


INTRODUCTION

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Heat Resisting TypesWhile even the GeneralEngineering irons do have somegood heat resisting properties, theheat resisting types of Meehaniteare specifically produced to meet awide range of high temperatureservice conditions.

Sub-division is on the basis oftype of application, but ischaracterized by structure, thus:Type HR

–carbidic/pearlitic (heat withwear).

Type HS–nodular graphite, ferritic.(temperature up to 1800°F(981°C).

Type HSV–nodular graphite, ferritic/pearlitic.

Type HE–flake graphite, pearlitic (heatshock).

Corrosion Resisting TypesThis series is sub-divided verybroadly according to structure, but composition may be variedconsiderably to suit exact condi-tions of service. This should bedone on the basis of consultationwith your casting supplier.

The austenitic nickel types CRand CRS may be modified to meetall standard engineering societyspecifications for this type ofmaterial.Type CC

–flake graphite, pearlitic.Type CR

–flake graphite, nickel/austenitic.

Type CRS–nodular graphite, nickelaustenitic.

Type CHS–nodular graphite, ferritic.

Almanite WSH rod mill guides Ductliron sprocket for ship engine


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Ductliron®, a registeredMeehanite trade-name for agroup of high carbon ferrousmaterials containing graphite inthe form of nodules or spheroidsis also known as ductile iron andnodular iron.

This versatile engineeringmetal possesses high strength,ductility, castability and otherproperties that make it outstand-ing for many of industry’stoughest applications.

Four types of MeehaniteDuctliron for GeneralEngineering purposes areavailable: SP 80 (SP 600), SH 100(SH 700), SF 60 (SF 400) and AQS.

They offer a full range ofmatrix structures and properties,as shown on the following pages.

Meehanite Nodular Graphite “S” Types (Ductliron®)

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GENERAL ENGINEERING/NODULAR GRAPHITE

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Meehanite Type SF 60 (SF 400)This type possesses high ductility,exceptional resistance to shockand provides maximum toughnessand machinability. Its structure isessentially ferritic and it is notreadily flame hardened.

This material meets therequirements outlined in thefollowing specifications:

ASTM A536 (60-40-18, 65-45-12)ASTM: A395 (60-40-18)ASME: SA395ASM: 5315*2

Typical Applications:For components subjected to

both thermal and mechanicalshock and for pressure castings,valves, cylinders, parts for auto-motive, machine tool, marine andwhere soft-steel castings, steelweldments or malleable iron hasbeen used.

MEEHANITE TYPE SF60 (SF400)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 60,000 (>400)Yield strength (tension)–psi (N/mm2) 40,000 (>310)Yield strength (compression)–psi (N/mm2) 54,000 (>370)Modulus of elasticity (tension), 106 psi (E x 106) 23 (0.17)Modulus of elasticity (torsion), 106 psi (N x 106) 9.5 (0.07)Elongation in 2˝ or 50 mm bar, min % 15-20 15-20Endurance limit (unnotched) psi (N/mm2) 0.50 0.50

(45° notch) 0.35 0.35Poisson’s ratio 0.32 0.32Brinell hardness range, BHN 140/190 140/190Impact strength–Charpy,

ft lbf (N/m) 10 mm2 bar “V” notch 7-15 (9.81-20.60)Specific gravity 7.18 7.18Solid contraction in/ft (mm/n) 1/32-3/32 (13)Patternmaker’s shrinkage, % 0.20-0.80%



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Meehanite Type SP 80 (SP 600)This type possesses in the as-castcondition more than twice thestrength of conventional gray castiron in combination withexceptional toughness.

It has a predominantly pearliticstructure and is readily machin-able. It responds easily to surfacehardening by nitriding or by flameor electric induction heattreatment.

This material meets the require-ments outlined in the followingspecifications:

ASTM: A536 (80-50-06)MIL: 1-11466BASM: 5316

Typical Applications:Recommended for use where

severe stresses, shock or highinternal pressures are encountered,such as heavy duty gears,sprockets, crankshafts, connectingrods, cams, car journal boxes,differential housings, compressorcylinders and components forheavy machinery, diesel, auto-motive and related industries.

MEEHANITE TYPE SP80 (SP600)Properties (As Cast) English SI UnitTensile strength, min., psi (N/mm2) 80 550Yield strength (tension), min., psi (N/mm2) 60 410Yield strength (compression), min., psi (N/mm2) 72,000 500Modulus of elasticity (tension), min., x 106 psi (E x 106) 25 0.18Modulus of elasticity (torsion), min., x 106 psi (N x 106) 9.6 0.07Elongation in 2 in. or 50 mm bar, min., % 3-10 3-10Endurance limit, unnotched, psi (N/mm2) 39,000 (269)Endurance ratio, unnotched 0.49 0.49Endurance ratio, 45° notch 0.35 0.35Poisson’s ratio 0.37 0.37Brinell hardness range, BHN 170/230 170/230Impact strength–Charpy,

ft lbf (N.m) (10 mm2 bar “V” notch) 1-5 (1.37-6.87)Specific gravity 7.20 7.20Solid contraction, in/ft (mm/m) 1/16-1/8 6-13Patternmaker’s shrinkage allowance, % 0.50%-1.00%



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Meehanite Type SH 100 (SH 700)Characterized by its exceptionalhardenability. Type SH 100 (SH 700) is particularly suitedwhere high strengths are desiredin relatively heavy sectioncastings.

In the as-cast condition, SH 100(SH 700) has a fully pearliticstructure. Any hardness value maybe obtained ranging from that of afree machinable iron to that of thefully hardened tool steel.


ASTM: A536 (100-70-03)MIL: 1-11466

Typical Applications:Specify for hard wearing

castings requiring increasedstrength and hardness over that inthe as-cast condition: heavy dutygears, spinning mandrels, pumpliners, rolls, dies, clutch drums,pistons, brake drums, agriculturalimplement parts.

MEEHANITE TYPE SH100 (SH700)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 100,000 >700Yield strength (tension)–psi (N/mm2) 70,000 >450Yield strength (compression)–psi (N/mm2) 85,000 >593Modulus of elasticity (tension), 106 psi (E x 106) 25 (0.18)Modulus of elasticity (torsion), 106 psi (N x 106) 4.8 (0.04)Elongation min., % in 2 in or 50 mm bar 3 min 3 minEndurance limit (unnotched) psi (N/mm2) psi 43,000 (297)Endurance ratio, (unnotched) 0.33 0.33

(45° notch) 0.25 0.25Poisson’s ratio 0.37 0.37Brinell hardness range, BHN 240-300 240-300Impact strength–Charpy,

ft lbf (10 mm2 bar “V” notch) 1-3 (1.37-4.12)Specific gravity 7.22 7.22Solid contraction, in/ft (mm/m) 1/8 -3/16 13/19Patternmaker’s shrinkage, % 1.0 -1.5% 1.0 -1.5%



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A good combination of hardness,strength and toughness can be hadby an oil quench from 1650°F(898°C) and drawing at 750°F(399°C).

The drawing temperature willrange from 400°F (204°C), to

1100°F (593°C), the lower tempera-ture sufficing to relieve hardeningstrains without reducing themaximum hardness value, whilethe 1100°F (593°C) draw will resultin hardnesses of approximately300 Brinell.

MEEHANITE TYPE SH100 (SH800)Properties (Heat Treated) English SI UnitTensile strength–psi (N/mm2) 100/170,000 (700/1190)Elongation, % 1-5 1-5Yield strength–psi (N/mm2) 70/130,000 (483/900)Brinell hardness range, BHN 260/340 260/340Impact strength–Charpy,

ft lbf (Joules/cm2) (10 mm2 bar “V” notch) 1-3 (1.36-4.07)

Pattern Makers Shrink 1.0 -1.5% 1.0 -1.5%

AQS

SH 100 (H.T.)

400204

500260

600315

700371

800428

900482

1000 °F538 °C

HA

RD

EN

ED

AS

CA

ST

0

40

80

120

160

200

TE

NS

ILE

ST

RE

NG

TH

, 10

00 x

psi

286

572

858

1144

1380

N/m

m2

TEMPERATURE, °F/°C

EFFECT OF QUENCHAND TEMPERING ON TENSILE STRENGTH

Figure 1



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Type SH100 (SH800) Meehanite three-way switch casting for overhead conveyor system requiring superior strength and wear resistance.

SH 100 (H.T.)

SP 80(SP 600)

AQS

400204

HA

RD

EN

ED

100

600B

HN

TEMPERATURE, °F/°C

EFFECT OF QUENCHAND TEMPERING ON HARDNESS

500260

600315

700371

800428

900482

1000 °F538 °C

200

300

400

500

Figure 2



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Meehanite Type AQSThis is an air hardening metalpossessing high strength,toughness and hardness.

It may be fully air quenchedthroughout casting section aftermachining to a wide range ofstrength and hardness values thatare uniform with little or no risk ofcracking or distortion.

Its endurance strength is higherthan most types of ductile ironand AQS also provides an excel-lent degree of abrasion resistancedue in part to its work hardeningcharacteristics.

Typical Applications:For components subject to

cyclic stresses of a high order andrequiring good wearing surfaces,such as crankshafts, cams, gears,and spinning mandrels or whereresistance to abrasion by non-metallics is mandatory, the highhardness and fatigue strength ofAQS is especially valuable. (Figure 3)

MEEHANITE TYPE AQSProperties (As Cast) English SI UnitTensile strength–psi (N/mm2) 80/180,000 (550/1240)Yield strength–psi (N/mm2) 70/140,000 (480/960)Elongation in 2˝ or 50 mm bar, min., % 1-3 1-3Brinell hardness range, BHN 225/500 225/500Impact strength–Charpy,

ft lbf (10 m2 bar “V” notch) (Joules/cm2) 1-3 (1.37-4.12)

Pattern Makers Shrink 1.0 -1.5% 1.0 -1.5%



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This 6680 lb. Meehanite mandrel was cast in type SH 100. Machined “as cast.” Hardened to 430-500 Brinell and then ground to size.

53,000 psi (365 N/mm2)

105

50

ST

RE

SS

, 10

3 psi

N/m

m2

NO. OF CYCLES

UNNOTCHED FATIGUE LIMIT OF AQS

55

60

106 107

345

380

414

Figure 3


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There are six types available.Their properties are presented inthe following pages.

Types GM 60 (GM 400), GA 50(GA 350), GC 40 (GC 275), GE 30(GE 200), GF 20 (GF 150), and AQhave been developed so as toprovide specific materials to meetthe broad requirements ofindustry.

They are unique in theircombination of physical proper-ties in so far as they bridge thegap between steel and cast iron,combining the most desirableproperties of each in varyingdegrees.

Meehanite Flake Graphite Types

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GENERAL ENGINEERING/FLAKE GRAPHITE

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Meehanite Type GM 60 (GM 400)This is the most versatile of thegeneral engineering types. It maybe cast uniformly solid to anysection thickness from 5/8˝ (16 mm) up to any reasonablecross-sectional dimension.

Having a dense, fine grainstructure, this material possessesexceptionally high physicalproperties including good impactstrength and shock resistance.

Machining to a very fine finishis recommended for heavy cast-ings where pressure tightness isrequired. Type GM 60 responds toheat treatment and may be surfacehardened by chilling, flame orinduction heat treatment.


ASTM: A48 (Class 60)ANSI: G25.1FEDERAL: QQ-1-652c

Typical Applications:Type GM 60 has replaced both

steel castings and forgings, hightensile bronzes and other non-ferrous materials where itsparticular combination ofproperties is advantageous.

It is used extensively for heavyservice gears, sheaves, cabledrums and crane wheels, kiln tiresand rollers, stamping, drawing,pressing, blanking and headingdies; lathe spindles, chucks, ballmill heads and gudgeons,hydraulic cylinders and rams;crankshafts, high pressure cham-bers and valves; straightening,bending and shaping rollers, etc.

MEEHANITE TYPE GM60 (GM400)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 55,000 (400)Proportional limit–psi (N/mm2) 0.01% permanent set 25,000 (179)Modulus of elasticity, 106 psi (E x 106) 21.5 (0.15)Modulus of rigidity, 106 psi (N x 106) 9.5 (0.07)Poisson’s ratio 0.33 0.33Modulus of rupture–106 psi (N x 106) 93,000 (640Compression strength–106 psi (N x 106) 200,000 (1379)Fatigue strength–106 psi (N x 106) 25,000 (172)Shear strength–106 psi (N x 106) 53,000 (366)Impact strength–Charpy, ft lbf (N.m) 8.0 (10.8)Single impact–Izod 0.79˝ (20 mm) Dia. Unnotched Bar 30-40 (41.2-55.2)Brinell hardness range, BHN 210/280 210/280Machinability rating 50 50Torsional strength–0.75˝ Dia. x 14.5˝ Long (19 mm x 368 mm)

Ultimate Torsional Fiber Stress 65,000 (448)Degrees Twist 99.3 99.3

Specific gravity 7.34 7.34Solid contraction, in/ft (mm/m) 5/32-6/32 (13-16)Patternmaker’s shrinkage, % 1.1-1.5 1.1-1.5Thermal properties see page 54Electrical properties see page 67



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Meehanite Type GA 50 (GA 350)This is a general utility ironcombining high strength,toughness, wear resistance andmachinability. Solid and depend-able castings can be made to anythickness over 1/2˝ (12.7 mm).

If designed with goodjudgment, it can be used to replacecertain steel forgings, steel castingsand weldments to good advan-tage. Because of its structuralhomogeneity, GA 50 retains highdimensional accuracy in service. It responds to heat treatment andmay be hardened locally or on thesurface by either flame or theinduction process.



Typical Applications:Outstanding examples of its use

occur in machine tool tables,saddles, racks and chucks, etc.,press and drawing dies (cast toform), compressor and dieselengine cylinders and liners;camshafts and crankshafts; alsohigh pressure castings attemperatures up to 700° (371°C).

MEEHANITE TYPE GA50 (GA350)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 50,000 (350)Proportional limit–psi (N/mm2) 0.01% permanent set 20,000 (138)Modulus of elasticity–106 psi (E x 106) 20 (0.14)Modulus of rigidity–106 psi (N x 106) 8.75 (0.06)Poisson’s ratio 0.32 0.32Modulus of rupture–106 psi (N x 106) 90,000 (621)Compression strength–106 psi (N x 106) 180,000 (1242)Fatigue strength–106 psi (N x 106) 22,000 (152)Shear strength–106 psi (N x 106) 50,000 (350)Impact strength–Charpy, ft lbf (N.m) 7.2 (9.8)Single impact–Izod 0.78˝ (20.3 mm) Dia. Unnotched Bar 25/35 (34/48)Brinell hardness range, BHN 190/250 190/250Machinability rating 48 48Torsional strength–0.75˝ Dia. x 14.5˝ Long (19 mm x 368 mm)


Specific gravity 7.31 7.31Solid contraction in/ft (mm/m) 1/8-5/32 13/16Patternmaker’s shrinkage, % 1.0 -1.4 1.0 -1.14Thermal properties see page 54Electrical properties see page 67



25

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Meehanite Type GC 40 (GC 275)This is an all-around versatile ironfor small and medium sizecastings.

It may be cast uniformly solid incastings varying from 3/8˝ to 21⁄2˝(9.5 to 51 mm) thick. Combininggood strength with low coefficientof friction and self-lubricatingproperties, Type CG 40 finds wideapplication in engineering compo-nents where metal-to-metal frictiondevelops thermal shock, such asheavy brake drums, clutch plates,pistons and cylinder liners, etc.

Because of its relatively highdensity and solidity, it is particu-larly suited to small types ofpressure castings where sectionaldimensions do not exceed 21⁄2˝ (64 mm).



Typical Applications:Excellent for use in machine

tool beds, head stocks, tables,press frames, bed plates, crank-cases, flywheels, engine cylindersand small cylinder liners, brakedrums, clutch plates, cams, pis-tons, pulleys, hydraulic valves.

This type finds general use dueto its useful combination of goodall-round properties with adapt-ability to large or small quantityproductions.

MEEHANITE TYPE GC40 (GC275)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 40,000 (275)Proportional limit–psi (N/mm2) 0.01% permanent set 14,500 (100)Modulus of elasticity–106 psi (E x 106) 16.5 (0.11)Modulus of rigidity–106 psi (N x 106) 7.25 (0.05)Poisson’s ratio 0.30 0.30Modulus of rupture–106 psi (N x 106) 80,000 (600)Compression strength–psi (N/mm2) 150,000 (1,035)Fatigue strength–psi (N/mm2) 17,500 (117)Shear strength–psi (N/mm2) 40,000 (300)Impact strength–Charpy, ft lbf (N.m) 4.5 (6.2)Single impact–Izod 0.78˝ (20 mm) Dia. Unnotched Bar 12/20 (17/28)Brinell hardness, BHN 170/230 170/230Machinability rating 47 47Torsional strength–0.75˝ Dia. x 14.5˝ Long (19 mm x 368 mm)


Specific gravity 7.25 7.25Solid contraction in/ft (mm/m) 7/64 -5/32 11/16Patternmaker’s shrinkage, % 0.9-1.3 0.9-1.3Thermal properties see page 54Electrical properties see page 67



26

Meehanite Type GE 30 (GE 200)This material is available as analternative and superior materialfor all applications replacingordinary gray cast iron.

Type GE 30 is manufacturedunder the same strict control asthe other Meehanite types andtherefore offers the benefits ofstructural uniformity and sound-ness. It permits higher feeds andspeeds because of the uniformityand complete absence of hardspots, corners and edges.

Type GE 30 (GE 200) combines

improved strength and densityand assures uniform dependableperformance.



Typical Applications:Suitable for any size casting

from the lightest repetitive to thelarge heavy individual casting.

MEEHANITE TYPE GE30 (GE200)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 30,000 (2000)Proportional limit–psi (N/mm2) 0.01% permanent set 11,500 (79)Modulus of elasticity–106 psi (E x 106) 13 (0.097)Modulus of rigidity–106 psi (N x 106) 5.5 (0.038)Poisson’s ratio 0.27 0.27Modulus of rupture–psi (N/mm2) 61,000 (421)Compression strength–psi (N/mm2) 120,000 (840)Fatigue strength–psi (N/mm2) 13,500 (93)Shear strength–psi (N/mm2) 30,000 (210)Impact strength–Charpy, ft lbf (N.m) 2.1 (2.9)Single impact–Izod 0.79˝ (20 mm) Dia. Unnotched Bar 6/12 (7.9/15.7)Brinell hardness, BHN 160/210 160/210Machinability rating 38 38Torsional strength–0.75˝ Dia. x 14.5˝ Long (19 mm x 368 mm)

Ultimate Torsional Fiber Stress 38,000 (262)Degree Twist 49.2 49.2

Specific gravity 7.06 7.06Solid contraction in/ft (mm/m) 1/10-1/8 (10/13)Patternmaker’s shrinkage, % 0.8-1.2 0.8-1.2Thermal properties see page 56Electrical properties see page 58



27

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Meehanite Type GF 20 (GF 150)This material is designedprincipally for high machinabilityand is used where ultimatestrength is not an important factor.For maximum machinability, anannealing treatment may also bespecified although this metalbecause of its excellent foundrycharacteristics is free from hardspots and edges even in compara-tively light sectioned castings.

It also possesses a high damp-ing capacity and is thereforeuseful where vibration and noiseof operation may be underconsideration.

Typical Applications:Recommended for components

requiring high machinability.

MEEHANITE TYPE GF20 (GF150)Properties (As Cast) English SI UnitTensile strength–psi (N/mm2) 20,000 (150)Proportional limit–psi (N/mm2) 0.01% permanent set 9,500 (66)Modulus of elasticity–106 psi (E x 106) 9 (0.062)Modulus of rigidity–106 psi (N x 106) 4 (0.028)Poisson’s ratio 0.24 0.24Modulus of rupture–psi (N/mm2) 41,000 (283)Compression strength–psi (N/mm2) 90,000 (621)Fatigue strength–psi (N/mm2) 11,000 (76)Shear strength–psi (N/mm2) 21,550 (149)Impact strength–Charpy, ft lbf (N.m) 1.5 (1.96)Single impact–Izod 0.79˝ (20 mm) Dia. Unnotched Bar 4/9 (5.9/12.8)Brinell hardness, BHN 150/200 150/200Machinability rating 30 30Torsional strength–0.75˝ Dia. x 14.5˝ Long (19 mm x 368 mm)

Ultimate Torsional Fiber Stress 31,000 (207)Degree Twist 35 35

Specific gravity 6.80 6.80Solid contraction, in/ft (mm/m) 5/64-1/8 (8/13)Patternmaker’s shrinkage, % 0.60/1.00 0.6/1.00Thermal properties see page 56Electrical properties see page 58


AS

QU

EN

CH

ED

AS

CA

ST

CONVENTIONALCAST IRON

400

500

BH

N

DRAWING TEMPERATURE, °F/ °C

300

200

400 600 800 1000 1200200°F

93°C 204 315 426 538 648


28

Meehanite Type AQThis is a wear and abrasionresisting iron that is readilymachinable “as-cast,” but may be“air hardened” after machiningwith little or no risk of cracking or dimensional change.

Heat treatment is simpleconsisting of cooling by air blastfrom a temperature of 1650°F(898°C).

Castings may also be locallyhardened for improved service ofworking faces or edges of suchparts as dies, punches, cams androllers, etc.

Retaining a good hardness“hot”, as shown by the chart(Figure 4), this material especially

recommends itself where abrasionresistance is required at elevatedtemperatures up to 1000°F (538°C).

Typical Applications:Components requiring good

strength and abrasion resistance,such as are used in conveyor androad making and agriculturalequipment, etc. Type AQ is highlyrecommended for parts that mustbe machined and subsequentlyhardened without distortion suchas cams, spinning mandrels,sheaves, wheels, dies, punches,rollers, engine liners and forequipment in service at elevatedtemperatures up to a dull red heat.

Figure 4

MEEHANITE TYPE AQProperties As-Cast Heat TreatedTensile strength–psi (N/mm2) 50,000 (345) 65,000 (448)Fatigue strength–psi (N/mm2) Unnotched 30,000 (207)Brinell hardness, BHN Up to 280 Up to 500Thermal properties See page 54Magnetic Properties See page 67



29

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Two Meehanite halves of an outer head cover for turbine. Castings weigh 53,000 pounds each.


30

Wear is a general term, not aspecific property of a material thatcan be expressed in absolute units.

It does not exist apart fromconditions in service and so far asmetals are concerned, selectionmust be determined by the limit-ing mechanical abrasive condition.

This means that exact condi-tions of service must be known if that material is to be selectedwhich will give maximum life at lowest cost.

Broadly, abrasive wearconditions can be placed in threegroups . . .

a. metal to metal, wherelubrication is not involved;

b. erosion, where suspendedsolids are carried in a liquidor gas;

c. dry abrasion, such asinvolved in the crushing ofmaterials, etc.

It must be recognized, however,that there is no clear line of demar-cation between these groups andthat experience or good judgementis necessary when one overlapsthe other.

There are three types ofMeehanite Metal recommendedfor abrasive applications: Types W,WS, WSH. Type W is further subdivided into W1, W2, and W4

according to the microstructure.These abrasion-resistant metals

trade-named “ALMANITE”, offerpractically any combination ofhardness and toughness.

For more detailed informationthan is presented on the followingpages, refer to Bulletin 60. Copiesavailable upon request.

Meehanite Metal Abrasion or Wear Resisting Types (Almanite®)

R


ABRASION RESISTING

31

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Meehanite Type W (ALMANITE®)This is a series of austenitic-martensitic white irons character-ized by high hardness andrelatively good impact strength.

ALMANITE W has better wearresistance than nickel-chromiumwhite irons and is a most econom-ical material for general purposeabrasion resistant applicationsinvolving scratching with slightimpact, as encountered in endliners, wear shoes, sand-pumpimpellers and similar parts.

ALMANITE W is convenientlyseparated into Types W1, W2 andW4. All of these are white ironswith excess carbon in the form ofhard wearing carbides.

Type W1 has a pearlitic matrix;W2 has a martensitic matrix, andW4 is highly alloyed to provide anaustenitic matrix in the as-castcondition which may be further

modified to give a martensiticmatrix by heat treatment or byfreezing.

Hardness values above 650Brinell result from this treatmentand, in the as-cast condition,machining . . . while still difficult . . . is considerably easier than inany other white iron.

The carbides in W4 are of thetrigonal and orthorhombic typegiving it a toughness higher thanthat usually associated with whiteiron.

Typical Applications:Recommended for severe

abrasive wear, dry or wet, withmoderate impact: liners, mullerwheels, pan bottoms, pug-millknife blades, wear shoes, andsand-pump impellers, etc.

MEEHANITE TYPE W (ALMANITE)Properties (As Cast) English SI UnitType W1Tensile strength, min, psi (N/mm2) 50/60,000 (345/414)Impact strength, 1.2 in. Izod, ft lbf (30 mm Izod, N.m) 30-50 (39-69)Brinell hardness range, BHN 500-600 500-600Microstructure Pearlitic

Type W2Tensile strength, min, psi (N/mm2) 50/60,000 (345/414)Impact strength, 1.2 in. Izod, ft lbf (30 mm Izod, N.m) 40-60 (59-79)Brinell hardness range, BHN 500-600 500-600Microstructure Martensitic

Type W4Tensile strength, min, psi (N/mm2) 60/80,000 (345/550)Impact strength, 1.2 in. Izod, ft lbf (30 mm, Izod, N.m) 40-70 (59-156)Brinell hardness range, BHN 400-700 400-700Microstructure High alloy austenitic

(as-cast)Martensitic

(heat treated)


ABRASION RESISTING

32

ALMANITE WS is a martensiticiron with free carbon in thenodular form.

The hardness value of WS islower than that of Type W, but thisis accompanied by a very highimpact strength three to four timesthat shown by competitivematerials, with improvedresistance to metal flow and wear.

ALMANITE WS is an idealmetal to use for service conditionsinvolving high impact andabrasion.

ALMANITE WS can be machinedby conventional means, but withdifficulty. It may be rendered moremachinable by an anneal at 1600°F(871°C) followed by a slow cool inthe furnace. After machining, it isnecessary to normalize or airharden to produce high hardnessvalues.

Typical Applications:Crusher jaws, crusher rings and

rolls, liners of all types, hammersin impact, pulverizers, slusher-scraper parts, etc.

Meehanite Type WS (ALMANITE®)

MEEHANITE TYPE WS (ALMANITE)Properties English SI UnitTensile strength–psi (N/mm2) 60/80,000 (414/552)Yield strength–psi (N/mm2) 50/65,000 (345/448)Modulus of elasticity–106 psi (E x 106) 24 (0.17)Elongation, % 2-4 2-4Brinell hardness, BHN 400/525 400/525Impact strength–1.2˝ Izod, ft lbf (30 mm Izod, N.m) 180 (up to 245)Impact strength–Charpy unnotched ft lbf 20

Almanite WS coalpulverizer rings


ABRASION RESISTING

33

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ALMANITE WSH is an austeniticnodular iron possessing superiortensile strength, toughness andability to work harden under con-ditions of severe pounding impact.

It has the same basic character-istics as austenitic manganesesteel, but it has a much superioryield point and a lowerelongation.

It may be regarded as anextension of Type WS for usewhere shock and stresses inservice are unusually severe.

Type WSH is extremely difficultto machine. Procedures used foraustenitic manganese steels shouldbe followed. It is conventional tofinish grind wherever possible.

Typical Applications:Crusher liners, hammers,

wearing blades, dredge buckets,dipper teeth, etc.

Meehanite Type WSH (ALMANITE®)

MEEHANITE TYPE WS (ALMANITE)Properties English SI UnitTensile strength–psi (N/mm2) 100,000 (690)Yield strength–psi (N/mm2) 75,000 (517)Elongation, % 4-10 4-10Brinell hardness, BHN 350-500 350-500Impact strength–1.2˝ Izod, ft lbf (30 mm Izod, N.m) 120 (up to 167)

In service in a crusher installation 1100 lbs (500 kg), ALMANITE WSH jaw crusher castingsof the type shown above are used to crush 8˝ (203 mm) rock to 11⁄2˝ (38 mm) size in a singlepass. They have worked for 57 days, crushing for 8 to 10 hours per day at 100 tons per hourwithout substantial wear.


34

Selection of the most suitablematerial to withstand the variousconditions of heat influence inservice presents unusual problemsbecause of the varied temperatureand corrosive gases encountered.

These conditions may includethermal shock (rapid heating andcooling)–continuous heating (scaling and growth)–low or hightemperature effect, local flameimpingement under high or lowpressures–contact with gases,chemicals or metals and so on.

Unfortunately, no one materialhas yet been developed suitable tomeet all of these conditions andvery often a compromise must bemade in order to meet a particularservice requirement.

To meet these varied conditions,Meehanite has developed anumber of Heat Resisting irons,each having a different combina-tion of properties.

The Meehanite metals aredesignated:

Type HSV, HS, HR, and HE andare divided into two main classes.

Class 1.Castings Subjected to ThermalShock (Rapid heating andcooling). Type recommended forthis service is HE. The individ-ual characteristics and industrialuses of each of these will bedealt with separately.Class 2.Castings Subjected toContinuous Heating (Scale andgrowth resistance). Typesrecommended for such serviceare HS, HR and HSV.There are, of course, certain

conditions of service that overlapbetween each group. Choice mustbe made only with full considera-tion of actual service requirements.

Up to 750°F (400°C)In this temperature range, all

types of Meehanite Metal will per-form satisfactorily. It is customaryto use the General Engineeringtypes rather than the special HeatResistant types. It is not particu-larly important whether heatingconditions are steady or cyclic.

Meehanite Heat Resisting Types

R


HEAT RESISTING

35

R

750°F to 1250° (400°C to 675°C)At temperatures above 750°F

(400°C), the loss of hardness andstrength in all metals is quite rapid.As creep strength is considerablymore important in this range, very

little emphasis is given to short-time mechanical strength values.

Values given are typical forvarious types of Meehanite Metalsuitable for use in this range.(Figure 5)

TABLE 1 TYPICAL HARDNESS VALUES FOR MEEHANITETemperature Brinell Hardness

°F (°C) GA 50 GC 40 HR750 (399) 225 212 288900 (482) 205 197 260

1000 (538) 182 180 2301100 (593) 139 134 1761250 (675) — — 133

HSHR

GA 50

TE

NS

ILE

, psi

x 1

03

N/m

m2

TENSILE STRENGTH FROM 750°F to 1250°F(399°C to 675°C)

40 276

454°C

850°F

30

20

207

138

510

950

565

1050

620

1150

675

1250

SF 60(SF 400)

SP 80(SP 600)

SH 100(SH 700)

SF 60(SF 400)

El.

TE

NS

ILE

, psi

x 1

03 (

N/m

m2)

ELO

NG

ATIO

N %

ELONGATION & TENSILE STRENGTH OFMEEHANITE METAL

80(552) 60

426°C

800°F

538

1000

648

1200

70(483)

60(414)

50(345)

40(276)

30(207)

50

40

30

20

10

Figure 5

Figure 6


HEAT RESISTING

36

Resistance to plastic flow orcreep is a major design considera-tion in the 750°F to 1250°F (399°Cto 677°C) range.

While the General Engineeringtypes are not normally consideredfor use in the upper end of thisrange, the “S” types of Meehanite,in particular, have good tensilestrengths and data on these ofshort-term tensile is given in

Figures 5 and 6.The heat resistant types “HR”,

“HS” are recommended for use inthe upper region of this tempera-ture range because of their overallheat resisting ability.

Creep is usually expressed asthe stress to rupture at varioustemperatures for various times.This is shown in Figure 7.

SF

SPSH

HRHS

N/m

m2

x 103

LARSEN MILLER PARAMETER, T 120 + log II, T in °K, t in Hours

100

5

°F

690

10 15 20 25 30 35

69

6.9

90

7080

60

50

40

30

2020

109

78

65

4

3

2

1

PS

I x 1

000

°C2050

100

150

200

250

300350

400

450

500

550

600

650

700

750

800

850

900

950

1000

1050

1100

1150

1200

1250 TIME – HOURS

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

1900

2000

2100

2200

2300

CREEP VALUES FOR MEEHANITE METAL(Stress to Rupture)

100,00010100

1,000

10,0000.1 1

10 510 4

10 310 2

10 1

10 0

10 -1

Figure 7


HEAT RESISTING

37

R

Surface CrazingSome surface crazing may occur

at the upper end of this tempera-ture range, particularly if the rateof temperature change is severe.

In general, the denser, higherstrength engineering metals–GM 60 (GM 400), GA 50 (GA 350),SP 80 (SP 600), and SH 100 (SH 700) are most resistant tosurface crazing at temperatures up to 1250°F (675°C).

Examples of GA 50 (GA 350)Meehanite compared to soft andchilled cast irons in a special testfrom 1200°F (649°C) are shown.

Surface oxidation in tempera-tures up to 1250°F (675°C) is notnormally a serious consideration.The “S” types of Meehanite aremore resistant than the “G” typesbecause the rounded graphiteretards oxide penetration from the surface.

TEST RESULTS SHOW RESISTANCE OFTYPE GA MEEHANITE TO SURFACE CRAZING.

CHILLEDIRON

SOFT CASTIRON

TYPE GA50


HEAT RESISTING

38

1250°F to 1600°F (675°C to 870°C)Loss of strength and hardness

above 1250°F (675°C) is quitesevere in all metals. In designinvolving load at these tempera-tures, allowance must be made forlow bearing capacities.

Despite low strength values,Meehanite Metal types “HR”,

“HS” and “HSV” are giving goodservice as dies in hot forming oftitanium and other metals in thistemperature range and higher.

Short-time tensile strength of“HS” and “HSV” Meehanitevaries according to the curvesshown below. (Figure 8)

HS

HSV

1200°F

TE

NS

ILE

, psi

x 1

03

N/m

m2

TEST TEMPERATURE SHORT-TIME HIGHTEMPERATURE STRENGTH

15 103

10 67.0

5 34.5

0

20649°C

138760

1400 1600

871

HR

HS

SOFT CAST IRON

SF 60(SP 400)

GR

OW

TH

IN

in/

in (m

m/m

m)

TIME IN HOURS AT 1600°F (870°C)

0.015

100

0.010

0.005

0

-0.005

0.020

200 300

Figure 8

Figure 9


HEAT RESISTING

39

R

As 1600°F (871°C) temperatureis within the plastic range, flowunder load becomes quite rapid.Creep data on types “HR” and“HS”, the only types recommend-ed for service involving mechan-ical loads, is given. (Figure 9)

Surface crazing can occur inthis range to a more markeddegree and where cyclic tempera-tures influence occurs, a fullanneal is always recommendedbefore the casting is put intoservice. Of particular interest isthe excellent behavior ofMeehanite Metal for glass moldsand plungers.

Oxidation and scaling canbecome severe in the 1600°F(871°C) temperature range. Thescale resistant ability of Types“HS”, “HSV” and “HR” isexcellent under most conditions.

The behavior of Type “HS”Meehanite is well illustrated in aspecial test conducted where asample is repeatedly heated to andcooled from 1600°F (871°C) in anoxidizing atmosphere. (Figure 10)

Type “HS” forms a tight adher-ing oxide scale that effectivelyprevents further deterioration dueto oxide penetration towards thecenter of the sample.

Figure 10

Type HS Meehanite casting heated to andcooled from 1600°F (871°C) for a period of

300 hours shows no growth or scaling.

Alloy iron casting given same test showsconsiderable growth and scaling.


HEAT RESISTING

40

1600°F to 1800°F (871°C to 981°C)For temperatures in the rangeabove 1600°F (871°C), mechanicalproperties fall off so rapidly thatthey become of questionable usein design.

Selection of the right materialfor a given application becomes a matter of judgment based onproven experience in similarapplications.

For service in this range, onlytwo types of Meehanite arerecommended.

Type HS Meehanite, whichcompares very favorably from astrength standpoint with any heatresisting metal, is recommendedfor applications at temperaturesabove 1650°F (898°C) and underconditions of furnace gases andwhen intermittent heating andcooling and continuous heatingmay be encountered withoutthermal shock.

Type HE Meehanite is recom-mended for cyclic heatingapplications involving severeshock. Large, continuous graphiteflakes contained in the metalstructure dissipate heat stresses.Because of this, it has relativelymoderate mechanical strength-tensile–30,000 psi (207 N/mm2),compression–130,000 psi (897 N/mm2).

Manufacturing proceduresused give Type HE the optimumtype of structure. It is particularlysuited for applications such asingot molds, slag pots, bottlemolds, etc.

In bottle molds, it is customaryto densify the working ormachined surface of the mold bythe use of chills. Type HE, whenchilled, will give the desiredcombination of density and abilityto absorb heat stresses.

HS

1600

CO

MP

RE

SS

ION

YIE

LDS

TR

EN

GT

H, p

si x

10

3

N/m

m2

COMPRESSION YIELD STRENGTHOF MEEHANITE TYPE HS

10

20871

138

59

0 01700

926

1500°F

815°C

1800

981

Figure 11


HEAT RESISTING

41

R

Meehanite Type HS, (Ductliron®)Type HS compares very favorablyfrom a strength standpoint (Figure8) with any heat resisting metaland is recommended for applica-tions at temperatures up to 1800°F(981°C) under both conditions ofcyclic and continuous heatingwithout thermal shock.

Compositional adjustments aremade to suit the exact service

conditions. It machines easily andprovides maximum resistance toscaling and growth. (Figure 9)

Typical Applications:For blast furnace parts, boxes,

trays, dampers, doors and frames,hot gas valves, rails and skids,reduction pots, glass molds,annealing pots, drums, saggerbottoms, retorts, floor castings, etc.

MEEHANITE TYPE HSProperties English SI UnitTensile strength–psi (N/mm2) 60/100,000 (414/690)Yield strength–psi (N/mm2) 45/75,000 (310/517)Modulus of elasticity–106 psi (E x 106) 23 (0.16)Elongation, % 2-10 2-10Brinell hardness range, BHN 200/280 200/280Impact strength–Charpy, ft lbf (N.m) 10 mm2 bar “V” notch 1-7 (1.4-9.8)

Tube support made in Type HS Meehanite. Weight 500 pounds.


HEAT RESISTING

42

Meehanite Type HSVThis is an iron developed essen-tially for engineering parts thatare subjected to long, continuousheating at temperatures up to1600°F (871°C). It has beendesigned to have the maximumload bearing ability.

Castings may be produced inany shape. They are readilymachinable, and possess an

excellent combination of proper-ties at room temperature as wellas good strength and hardness atelevated temperatures.

Typical Applications:Hot forming dies, turbo and

supercharger castings, furnaceparts.

MEEHANITE TYPE HSVProperties English SI UnitTensile strength–psi (N/mm2) 100/120,000 (670/828)Yield strength–psi (N/mm2) 50/80,000 (345/512)Elongation, % 2-10 2-10Brinell hardness range, BHN 200/280 200/280Thermal conductivity, 50°F-450°F (10°C-232°C)

°C/cm, btu/hr/ft, °F/in (cal/cm2/sec) 278 (0.095)Co-efficient of thermal expansion

per °F from 100°F to 1000°F(°C from 38°C to 538°C), x 106 6.7 (12.1)

Grate bars removed from service at temperature above 1200°F (648°C). Bar #1 is alloy steel (25% chrome – 12% nickel), Bar #5 is cast in HSV.

Note freedom from growth and distortion.


HEAT RESISTING

43

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Meehanite Type HRType HR is a strong, dense iron of high rigidity and excellentresistance to scaling under mostconditions. Type HR is non-growing for temperatures up to1350°F (734°C). It possesses goodload carrying ability.

Typical Applications:Recommended for service

conditions where intermittentheating and cooling and continu-ous heating may be encounteredwithout thermal shock–furnaceskid bars, stoker dead plates,stocker tuyeres and extensionplates, retorts, tube supports,furnace parts, etc.

MEEHANITE TYPE HRProperties English SI UnitTensile strength–psi (N/mm2) 40,000 (300)Compression strength–psi (N/mm2) (1,138)Modulus of elasticity, 106 psi (E x 106) 21 (0.15)Brinell hardness range, BHN 300/370 300/370Thermal conductivity 235 BTU/hr.ft.2 0.08 cal/cm.sec.°C

Meehanite type HS annealing basket used to support over 2000 lbs. of bar stock during heat treat cycles at 1450°F.


HEAT RESISTING

44

Meehanite Type HEThis material withstands rapidheating and cooling withoutpremature failure. HE is an all-around material for general use. It is also advantageous wheredimensional stability or a finemachine surface is required.

The constitution of this iron isso designed that the structure ofthe iron readily accommodatesitself to sudden changes ofthermal stress which cause rapidexpansion and contraction of the casting.

Type HE possesses a highdegree of refractoriness and auseful range of strength propertiesat various temperatures. It isfreely machinable in the “as-cast”condition.

Typical Applications:Ingot molds, slag pots, hot

plates, parts heated rapidly by anaked flame as in certain saltbaths, lead or zinc pots, sinteringgrates, pig casting machine parts,coke oven doors and liners, etc.

MEEHANITE TYPE HEProperties (Room Temperature) English SI UnitTensile strength–psi (N/mm2) 25,000 (172)Modulus of elasticity, 106 psi (E x 106) 14 (0.10)Brinell hardness, BHN (as-cast) 170/210 170/210

Meehanite Type HS bracket provides good heat resistance and resists warping.


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Sagger bottoms cast in Type HS resist scaling and warping at 1600°F.

Waste gas disposal headwall casting made in Type HS Meehanite provides excellent service at 1450F and higher.


46

Meehanite castings, in general,possess good corrosion resistingproperties compared with suchmaterials as steel and ordinarycast iron. In addition, they havethe advantage of density, solidityand uniformity of mechanicalproperties due to their purity,close-gained structure andcontrolled dispersion of graphite.

For mildly corrosive conditions,Type CC is an all-round inexpen-sive general engineering material,but for more severe corrosiveconditions, Types CR and CRSshould be used.

These types are austeniticnickel-bearing irons correspondingto ASTM Specifications A436 andA439 and for convenience arefurther sub-divided into typesaccording to these specifications.

Type CHS is a higher strengthmaterial recommended for use inacidic conditions at hightemperatures.

Corrosion is a complexphenomenon generally consideredto be electro-chemical in nature,

but being so dependent on exactenvironmental conditions thatcorrosion resistance can only beexpressed on a comparative basis.The unit of comparison is usuallyin mils per year, 1 mil = 0.001 in.

The rate of corrosion is affectedby concentration, temperature,rate of movement of the corrosionmedia, and by the tendency of themetal to become passive under theparticular conditions of corrosion.

Because of the general complex-ity of corrosive action, it is recom-mended that specific cases bediscussed directly with yourcasting supplier or with MeehaniteWorldwide who may have casehistories corresponding to yourapplication available in theirextensive engineering library.

The extent of corrosion thatmay be expected is best gaugedfrom test results on the behavior of Type CR (austenitic-nickel) invarious chemicals. Ranges givenvary because of concentrationaldifferences and are given only as a broad guide.

Meehanite Corrosion Resisting Types

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CORROSION RESISTING

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CHEMICAL mil/year mm/yearMINERAL ACIDS

Hydrochloric 10-370 0.25-9.40Sulphuric 5-50 0.13-1.30Nitric 70-2300 1.78-58.42Phosphoric 20-100 0.51-2.50

ORGANIC ACIDS 1-120 0.03-3.05

WATERFresh 0.06 0.001Salt 8-10 0.20-0.25Mine & Industrial 5-40 0.13-1.02

ALKALIESSodium Hydroxide 0.1-90 0.003-2.29Ammonia 0.05-90 0.001-2.29Calcium Hydroxide 0.2 0.006

CHLORIDESAmmonium 3-10 0.08-0.25Barium 40 1.02Calcium 1-4 0.03-0.10Sodium 0.04-4 0.01-0.10Zinc 20-80 0.51-2.00

SULPHATESAluminum 2-16 0.05-0.41Ammonium 0.07-6 0.002-0.15Copper 35-490 0.89-12.45Manganese 550 13.97Zinc 560 14.22

PAPER CHEMICALS 0.8-40 0.02-1.02

PETROLEUMCHEMICALS 0.1-400 0.003-10.16

Choice of Meehanite Types To Suit Corrosive Conditions

Mineral Acids: Type CC hasexcellent corrosion resistance to100% sulphuric acid at tempera-tures up to 250°F (121°C).Corrosion increases with increas-ing temperature and decreasingacid concentration. Types CR andCRS resist corrosion by cold dilutesulphuric acid.

Organic Acids: Types CR andCRS resist corrosion by acids suchas formic, acetic, oxalic, etc., betterthan low alloy gray irons.

Alkalies: Type CC is not corrod-ed by dilute alkali solutions at anytemperature. Hot solutions [above150°F (65°C)] exceeding 30% con-centration are mildly corrosive.

Industrial Waters: For industrialwaters of low acid concentration,Type CC is satisfactory. Types CRor CRS are used in applicationswhere the pH is low, or in stronglyacidic conditions. In applicationswhere the component is subject tohigh velocity or abrasion, Type CRor CRS should be specified.


CORROSION RESISTING

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While not considered corrosiveresisting in the normal sense, thisis a general utility material with aminimum of alloying elements togive an improvement in corrosionresistance over that which wouldnormally be expected from theGeneral Engineering types ofMeehanite Metal. It can be usedfor slightly acid solutions, alkalisolutions at temperatures up to150°F (65°C) and concentrated

sulphuric acid at temperatures upto 250°F (121°C).

Typical Applications:Acid pans, kettles, pumps,

valves, fittings, evaporators,condensers, retorts, filter presses,stills, reaction vessels, etc., forhandling chemicals, mine and seawater, carbonators, causticizers,and generally for solutions of lessthan 2 pH.

Meehanite Type CC

MEEHANITE TYPE CCProperties English SI UnitTensile strength–psi (N/mm2) 40,000 (276)Brinell hardness, BHN 190/230 190/230


CORROSION RESISTING

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Type CR is an austenitic materialespecially designed to meet a widevariety of corrosion, wear and heatapplications. It has flake graphiteand chemical analysis conformingto ASTM Specification A436-78.

Where ranges are broad andhigh at one end of the scale; e.g.,

copper sulphate, or ammonia, aclose look at the exact corrosionconditions is called for.

In general, Type CR is used forall applications, with modificationof CR types being used foroccasional special conditions ofservice.

Meehanite Type CR

MEEHANITE TYPE CRProperties English SI UnitTensile strength–psi (N/mm2) 25,000 (>172)Brinell hardness, BHN 130/180 130/180


CORROSION RESISTING

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This is an austenitic material withgraphite in the nodular form. It conforms to ASTM designationA439-80 and provides muchhigher strength than Type CR withexcellent resistance to corrosion,wear and heat.

The CRS types are approxi-mately the same as the CR typeswhen it comes to corrosionresistance, but they show excellentheat resistance and also havesuperior physical and mechanicalproperties.

Other properties, electricalcharacteristics and thermalproperties are available on requestfrom Meehanite Worldwide.

Typical Applications:Types CR and CRS are recom-

mended for components whichinvolve handling acid and alkalisolutions at temperatures up to1300°F (704°C) for abrasiveslurries, salt water and other heatand wear applications with orwithout corrosive media.

Meehanite Type CRS

MEEHANITE TYPE CRSProperties English SI UnitTensile strength, min, psi (N/mm2) 58,000 (>400)Yield strength, min, psi (N/mm2) 30,000 (>207)Elongation, % >8.0 (>8.0)


CORROSION RESISTING

This corrosion resistant type is ahigher strength material withgood shock resistance.Compositional adjustments aremade to suit exact serviceconditions.

Typical Applications:Types CHS is recommended for

use for components subjected toconcentrated sulphuric acid oroleum.

Meehanite Type CHS

MEEHANITE TYPE CHSProperties English SI UnitTensile strength, min, psi (N/mm2) 60/100,000 (414/690)Yield strength, min, psi (N/mm2) 45/75,000 (310/517)Modulus of elasticity, min, x 106 psi (E x 106) 23 (0.16)Elongation, % 2-10 2-10Brinell hardness range, BHN 200/270 200/270Impact strength, Charpy, ft lbf (N.m) (10 mm2 bar “V” notch) 1-7 (1.4-9.8)

Meehanite metal possesses good corrosion resisting properties and is used throughout the world for pumps, impellers, volutes and casings.

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52

Austempered ductile iron is aductile iron which is processed by alloying and special heattreatment. The heat treatmentrequires an interrupted quenchusually into a salt bath. The result-ing material has a combination ofexceptional strength and tough-ness, meeting and often exceedingthose of alloy steels.

Austempered ductile can bemade in sections up to aboutseven inches, but to achieve fullyAustempered microstructures insections over three and a halfinches, requires a specialized andproprietary Meehanite heat treat-ment process along with carefullycontrolled alloying.

For applications where wearresistance is the major issue, it is asimple matter to adjust the heattreatment to obtain higherhardness and strength values, butthis is achieved with somesacrifice to toughness. It shouldalso be remembered that thismaterial will work harden on thesurface, and so the material will,

under the right circumstances,wear better than the quoted hard-nesses would suggest, and soA.D.I. will often out wear othermaterials of the same hardness.

Typical applications for A.D.I.are where high strength is needed,and where excellent wear resis-tance and fatigue strength arerequired. Such an application isgears, and A.D.I. has been usedwith great success. This toughwork hardening material hasproved to be an excellent replace-ment for hardened steels. The useof A.D.I. can result in less weight,reduced number of components,and quieter running, becauseA.D.I. has a lower modulus thansteel, better face to face contactcan be achieved which reducesHertzien or contact stress on theteeth surfaces. Also A.D.I. willwork harden which adds to thecontact fatigue strength. As aresult, gear face widths anddiameters can be reduced whichwill make the gear run betteraxially and reduces weight, and at

Austempered Ductile Iron

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High Strength Nodular Corporate

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the same time provide betterprotection under overload condi-tions. The superior tribologicalproperties of A.D.I. have resultedin the elimination of bronze bear-ing bushings, and will allow thegears to run temporarily withoutlubrication. Due to the type ofmatrix structure, the softer gradesof A.D.I. can be shot-peened todouble the root fatigue strength.One caveat to be aware of is thatA.D.I. is not suitable for heatapplications where the servicetemperature will reach 350° C.

Another common applicationof A.D.I. has been crankshafts andaxles. The majority of sealed-for-life refrigeration units are madewith austempered crankshafts.Axle applications benefit from thematerials lack of notch sensitivity,

good fatigue strength, and reason-able machinability.

The railroad industry has animmense application both inretarders and rolling stock. A.D.I.is very popular for retarder brakeshoes, where its superior quiet-ness and wear resistance is wellreceived in urban semi residentialcommunities. A.D.I. brake beamshave also been shown to outlaststeel beams, and withstand thecold weather, at more than 20%less cost.

Another type of major use ofA.D.I. is for shells and projectiles.Also steel forged track shoes arebeing replaced with A.D.I. Trackshoes in A.D.I. have also beenvery successful both in military,construction, and earth movingequipment.

Other typical applications are:

Abrasive Protection Liners Ground Engaging ToolsBearing Sleeves Guide RollersBrake Shoes Hydraulic Pump BodiesBushing Sleeves Piston SleevesCable Drums PulleysCamshafts Pump ImpellersChain Sprockets Rack and Pinion GearingConnecting Rods Railroad Car WheelsCrankshafts Rollers and SprocketsCultivating Tools Shredder KnivesDifferential Spiders Steering KnucklesDrive Shafts Trolley WheelsEngine Mounting Brackets Wear Plates and GuidesFriction Blocks Wire Guides



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Machining of A.D.I. is generallyspeaking, possible, using normalmachining techniques. Only thetapping of small diameter holes(especially dead end) and scrapingof the softest type is very difficultdue to work hardening. It ishowever common practice tomachine to near final size andthen heat treat. This is possiblebecause the heat treatment is con-sidered “soft”, and the consequentvolume changes are small, andpredictable with volumeexpansion of between only 0.2% - 0.4%.

There are three specifications ofMeehanite austempered ductileiron and these are defined mostconveniently by their averagehardness values.

K300This is the softest of the threegrades, with the highestelongation and exceptional impactvalues. Though the tensilestrength is no higher than can beachieved with normal quenchedheat treated ductile. The muchhigher impact and elongationsmake this an attractive materialfor extreme applications. As thesoftest of the three grades with the highest content of austenite(30%-40%) it is the grade most

readily able to surface work hard-en and thus wear better than itshardness would suggest. Thoughall ductile irons benefit from shotpeening to improve fatiguestrength this material especiallybenefits from this practice.Bending fatigue strength is almostdoubled by shot peening and infact raised to the same levelachieved by the K500 Grade.This is an ideal material for gearsof all types, crankshafts, couplingsor any application where highimpact and fatigue strengths arerequired.

K400This is the middle grade specifiedfor high strength combined withmoderate elongation and impactvalues. Often specified forapplications such as differentialspyders, bearing rolls, annulartype gears, structural suspensionparts, disc brake rotors, retardershoes, axe heads.The ability to cast this materialinto complex shapes makes it aperfect replacement for manysteels reducing casting volumeand weights.

K500This is the hardest and strongestgrade specified at a minimum of230,000 psi but capable of reaching

Machining of A.D.I.



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Type K300 K400 K500

UTS (x 1000) 130 (900) 175 (1200) 230 (1600)

Yield (x 1000) 98 (675) 140 (960) 185 (1275)

% Elongation 8 - 14 4 -10 0 - 4

BHN 260 - 310 360 - 430 450 - 550

Endurance LimitUn Notched 63 (440) 74 (510) 85 (580)Notched 39 (270) 51 (360) 62 (430)

Endurance ratio 0.49 0.48 0.46

Charpy Unnotched ft. lbs. 75 - 90 45 - 70 0 - 40

Charpy Notched 5 - 7 4 - 6 1 - 5

Austempered Ductile Iron Properities

in excess f 250,000 psi, whilemaintaining impact values typicalof a regular pearlitic type ductileiron.This is a material designed forsevere wear applications, such ascrushing and grinding. It shouldbe understood that this material atits highest hardness will probablycontain some martensite which is

ideal for crushing and grindingapplications, but not for impact.To maximize impact resistance thematerial should be specified at thelower hardness ranges (i.e., 450 Hb - 500 Hb). In this form thematerial is even used for gears.Other applications includesnowplough runners, coal millhammers, and muller wheels.


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For every type of metal there is amaximum section thicknessbeyond which solidity andstrength properties fall. In foundryparlance, this is called “massinfluence.”

Mass influence results in opengrain, lack of density and drasticdecrease in unit strength in heaviersections, unless the metal hasadequate “solidity penetrationpower”.

This property is of great signifi-cance where high pressures are tobe encountered and where thedesign is to secure minimumweight with assured safety.

With the Meehanite process, the structure and strength arecontrolled to fit the sectionsinvolved in the casting with certainlimitations.

Where uniformity of solidity(density) and machinability arerequired, these sections are givenbelow in Table II.

Table III (see next page) displaysa simple chart permitting the selec-tion of the type of Meehanite Metalaccording to the tensile strengthand the thickness of the sections ofthe casting involved.

Effect of Section Thickness On Strength and Solidity

MeehaniteEngineeringData

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ENGINEERING DATA

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Assuming that certain require-ments indicate the section of thecasting will vary considerably; for example, from 1⁄2˝ (12.7 mm) to 3˝(76.2 mm) section can readily be castin Type GC and uniformity will beobtained in the 3˝ (76.2 mm) section,but the allowable stress value will bebased on a 35,000 psi (241 N/mm2)ultimate tensile value. However, if the3˝ (76.2 mm) section could be reducedto 2˝ (50.4 mm) and Type GA 50 (GA350) used, the allowable stress wouldbe based on a 40,000 psi (276 N/mm2)ultimate. Thus, by proper adjust-

ment of the minimum sectionand/or consideration of theultimate tensile value available inthe heaviest section, a decision canbe made as to type of metal whichis most economical and best to dothe job.

From these data, one can selectthe type of Meehanite Metal for aparticular casting which will resultin efficient use of both weight andthe available characteristics.

Further data on mass effect isavailable in B-58 MeehaniteCastings Quality Guide.

TABLE IIRECOMMENDED MINIMUM AND MAXIMUM CASTING SECTION

Type of Minimum MaximumMeehanite Casting Section Casting Section

in (mm) in (mm)GM 60 (GM 400) 3/4 (19) to 30 (762)GA 50 (GA 350) 1/2 (13) to 8 (203)GC 40 (GC 275) 1/4 (7) to 3 (76)GE 30 (GE 200) 1/8 (3) to 1.5 (38)GF 20 (GF 150) 3/32 (2) to 3/4 (19)SP 80 (SP 600) 3/8 (10) to 12 (305)SF 60 (SF 400) 1/4 (6) to 12 (305)

TABLE IIISELECTION OF TYPE OF MEEHANITE ACCORDING TO

CASTING THICKNESSUltimateTensileStrength in 1⁄4 1⁄2 1 2 3 4 6psi(N/mm2) mm 6 13 25 51 76 102 15275,000 (517) SF 60 SP 80 SP 80 SP 80 SP 80 SH 100 SH 10065,000 (448) SF 60 SF 60 SP 80 SP 80 SP 80 SP 80 SH 10055,000 (380) SF 60 GA 50 GM 60 GM 60 GM 60 GM 60 GM 6050,000 (345) GC 40 GC 40 GA 50 GA 50 GM 60 GM 60 GM 6045,000 (310) GC 40 GC 40 GA 50 GA 50 GA 50 GA 50 GA 5040,000 (276) GE 30 GC 40 GC 40 GA 50 GA 50 GA 50 GA 5035,000 (241) GE 30 GE 30 GC 40 GC 40 GC 40 GA 50 GA 5030,000 (207) GE 30 GE 30 GE 30 GC 40 GC 40 GC 40 GA 5020,000 (138) GF 20 GF 20 GE 30 GE 30 GE 30 GE 30 GC 40


ENGINEERING DATA

58

Thermal conductivity may bedefined as the heat-conductingpower of a uniform, or homoge-neous, substance per unit of cross-sectional area.

Values arrived at for thermalconductivity under controlledlaboratory testing methods may beused as a comparison betweendifferent materials, but they givelittle indication of how much heatconductivity power the metal willhave in a particular application.This is because the heat-conduc-tivity in service depends on manyfactors such as:

1. The rate of heat input.2. The temperature gradient

between the two walls of thecasting and the actualtemperature of the metal.

3. The shape of the casting.4. The condition of the surfaces

of the casting.5. The type of gas, liquid or

solid, that is supplying theheat units to the casting.

6. The thermal conductivity ofthe metal.

We see that in any heat conduc-tivity consideration, the thermalconductivity of the metal is only arelatively small factor.

In steam chests, for example, the importance of design, steamtemperature and flow rate, and thecondition of the casting surface areconsidered more important thanthe thermal conductivity of themetal comprising the chest.

In air-cooled engines, the designof the cooling fin is considered tobe the most important single factor.

The previous points have beenmade not to de-emphasize theimportance of the thermal conduc-tivity of the metal, but to illustratethat normally other factors aremore important to heat transferthan thermal conductivity.

With Meehanite Metal, both thechemistry and the microstructureaffect the thermal conductivitywith graphite content, siliconcontent, and matrix structure themost important factors.

Graphite has the highestconductivity of any constituent inMeehanite and increasing theamount of graphite increases thethermal conductivity.

Increases in carbon content willraise the thermal conductivity onlyif these increases enlarge thenumber or size of the graphiteflakes. If the carbon change resultsin an increase in the pearlite in thematrix, then thermal conductivityis decreased because the cementitecomposing the pearlite has a muchlower thermal conductivity thanferrite.

Flake graphite irons havegreater thermal conductivity thannodular irons, and a randomgraphite orientation conductsbetter than undercooled, or rosettegraphite.

The addition of almost all otheralloying elements lowers thethermal conductivity. Theseinclude silicon, manganese,phosphorus, aluminum, copper,nickel and chromium.Molybdenum and tungsten seemto give slight increases.

Thermal Conductivity


ENGINEERING DATA

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When both the silicon contentand the graphite are increased suchas when going from Type GA 50(GA 350) to Type GE 30 (GE 200),the effect of silicon on loweringthermal conductivity over-balancesan increase due to more graphite aslong as the matrix remainspearlitic. Ferritization of the matrixincreases the thermal conductivity.

For best thermal conductivity,specify a high carbon, fully ferriticflake iron such as GF 20 (GF 150)with low silicon and no other alloycontent.

However, since the thermalconductivity of the metal is usuallya minor point in the overall heattransfer of a component, the typeof Meehanite is more frequentlychosen for its other physicalproperties in preference to itsthermal conductivity.

Ingot molds are an exception tothis; however, and a high carboniron is chosen because of its highthermal conductivity.

Thermal conductivity is normal-ly expressed as either BTU’s perhour per square foot per degreeFahrenheit for one inch of thick-

ness, or calories per second persquare centimeter per degreeCentigrade for one centimeter ofthe thickness.

Conversion factors that may behelpful are as follows:

BTU/(hr) (ft2) (°F per in)x 0.00034 = gm-cal/(sec) (cm2)

(°C per cm)x 0.124 =kg-cal/(hr) (M2)

(°C per M)x 0.0833 =BTU/(hr) (ft2)

(°F per ft)Cal/(sec) (cm2) (°C per cm)

x 2941 =BTU/(hr) (ft2)(°F per ft)

Typical values for thermalconductivity at 100°C forMeehanite Metal are listed in Table IV.

Annealing to produce a fullyferritic matrix from a fully pearliticone increases the thermalconductivity by approximately0.01 cal/(sec) (cm2) (°C per cm) or30 BTU/(hr) (ft2) (°F per in).

Raising the mean temperatureof the metal from 100°C to 400°Clowers the thermal conductivity byapproximately 0.01 cal/(sec) (cm2)(°C per cm).

TABLE IVBTU/(hr) (ft2)

Type (°F per in) Cal/cm.sec.°CGM 60 323 0.108GA 50 290 0.112GC 40 325 0.120GE 30 365 0.127GF 20 365 0.131HR 210 0.080HE AS-CAST 298 0.100HE ANNEALED 332 0.130SF 60 249 0.090SP 80 221 0.085SH100 0.080


ENGINEERING DATA

60

When a solid material is subjectedto a change in temperature, itundergoes a change in volume,which corresponds to the magni-tude of the temperature variation.

This expansion is usuallyexpressed as inches per inch oflinear elongation.

The expansion of cast iron isquite complex. Irons may containferrite, carbides (either uncom-bined or in pearlite), free graphite,and varying amounts of inclu-sions, such as MnS. In addition,these irons may be heat treated oralloyed to produce ferritic,pearlitic, bainitic, martinsitic, oreven austenitic structures.

The behavior of cast iron isfurther complicated by a magneticchange in cementite, which occursat 210°C and the changes of crystalstructure, which occur as heatingprogresses.

Several factors also contributeto volume changes which, unlikethe reversible expansion, result ina permanent growth. Among themare structural changes such asdecomposition of pearlite andinternal oxidation.

As can be seen in the summarygraph, all Meehanite Metals(except austenitic CR), regardlessof structure or composition, initial-ly expand at about the same rate.This rate will fall in the area desig-nated as 1 on the graph (Figure 12)above 800°F (426°C); however, theexpansion is not so regular.

The expansion curves for theflake-type General Engineeringirons, GA 50 (GA 350), GC 40 (GC275), and GE 30 (GE 200) will fallin area 2. These materials undergoabrupt rate changes at the criticaltemperature above which theyexpand, as indicated in area 3.

Above 800°F (426°C) increasedalloy content decreases the rate ofexpansion, as does nodularity.Expansion curves for the follow-ing types of Meehanite lie in area4, AQ, GM 60 (GM 400), HS, SP 80(SP 600), and SH 100 (SH 700).

It is interesting to note thatquenching influences the rate ofexpansion only until the time atwhich the hardened structure hascompletely tempered, after whichexpansion is the same as in the as-cast condition. These rates are alsoapplicable upon recycling; theonly change will be a verticaldisplacement of the curves aftereach cycle due to the permanentgrowth.

Table V lists the approximaterates of expansion for some typicalMeehanite Metals.

The following are some generalobservations which are applicableto Meehanite Metal:

1. Increased carbon equivalentsresult in lower expansion innodular irons.

2. Nodularity results in a higherrate of expansion at lowtemperatures and a lower rate

Thermal Expansion


ENGINEERING DATA

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2

1

3

4

ELO

NG

ATIO

N,

(inch

per

inch

)

SUMMARY OF VARIOUS TYPES

.015

93°C

200°F

.014

.013

.012

.011

.010

.009

.008

.007

.006

.005

.004

.003

.002

.001

204

400

315

600

426

800

538

1000

648

1200

760

1400

871

1600

981

1800

Figure 12


ENGINEERING DATA

62

at high temperatures than thatof a flake iron of similarcomposition.

3. Alloys increase the rate ofexpansion to about 800°F(426°C), above which theydecrease the rate.

4. Manganese contents in excessof 0.8 percent have more effecton expansion than do copperand chromium. Likewise, theinfluence of copper is greaterthan that of chromium.

TABLE VAPPROXIMATE RATES OF THERMAL EXPANSION

ROOM TEMPERATURE TO °F/°C200°F 400°F 600°F 800°F 1000°F 1200°F 1400°F 1600°F

Type 93°C 204°C 315°C 426°C 538°C 648°C 760°C 871°Cin./in per °F x 10-6 (µm.n.k)

GE 30 5.85 5.95 6.35 6.80 7.90 9.05(10.53) (10.71) (11.43) (12.24) (14.22) (16.29)

GC 40 5.45 5.75 6.25 6.70 7.60 9.0(9.81) (10.35) (11.25) (12.06) (13.68) (16.20)

GA 50 5.05 5.35 6.10 6.50 7.20 7.80(9.09) (9.63) (10.98) (11.70) (12.96) (14.04)

GM 60 5.00 5.30 6.00 6.40 7.05 7.50 7.80 8.30(9.00) (9.54) (10.80) (11.52) (12.69) (13.50) (14.04) (14.94)

AQ 5.00 5.65 6.35 6.50 6.75 7.20 7.70 8.30(9.00) (10.17) (11.43) (11.70) (12.15) (12.96) (13.86) (14.94)

AQ (1) 6.65 9.40 10.95 9.75 8.15 8.20 8.40 9.10(11.97) (16.92) (19.71) (17.55) (14.67) (14.76) (15.12) (16.38)

AQ (2) 5.85 5.95 7.70 7.75 7.05 7.20 7.55 8.20(10.53) (10.71) (13.86) (13.95) (12.69) (12.96) (13.59) (14.76)

CR 10.00 10.20 10.40 10.20 10.10 10.30 10.60(18.00) (18.36) (18.72) (18.36) (18.18) (18.54) (19.08)

HR 5.85 5.95 6.15 6.35 7.15 7.75 8.25 9.30(10.53) (10.71) (11.07) (11.43) (12.87) (13.95) (14.85) (16.74)

HS 5.85 6.25 6.35 6.50 7.00 7.20 7.40 7.50(10.53) (11.25) (11.43) (11.70) (12.60) (12.96) (13.32) (13.50)

SP 80 5.85 5.95 6.15 6.40 6.85 7.05 7.25 7.35(10.53) (10.71) (11.07) (11.52) (12.33) (12.69) (13.05) (13.23)

SH 100 6.55 6.65 6.75 6.80 7.40 7.80 8.25 8.50(11.79) (11.97) (12.15) (12.24) (13.32) (14.04) (14.85) (15.30)

SF 60 5.85 6.10 6.25 6.50 6.95 7.10 7.35 7.40(10.53) (10.98) (11.25) (11.70) (12.51) (12.78) (13.23) (13.32)

AQ(1) WATER QUENCHEDAQ(2) AIR QUENCHED


ENGINEERING DATA

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The amount of heat required toraise a unit mass of material onedegree in temperature is called theheat capacity of that material.

The ratio of this amount of heatto that required to raise a unitmass of water one degree at somespecified temperature is thespecific heat of the material.

For most engineering purposes,heat capacities may be assumednumerically equal to specificheats. In general, specific heatvaries with temperature but formoderate ranges, a mean valuemay be taken.

While specific heat may not beregarded as important engineeringwise as thermal conductivity, orthermal expansion, it neverthelessis a factor that must be given someconsideration in certain engineer-ing applications involving heat.

Any material with a high spe-cific heat is capable of absorbingmore heat units before its temper-ature rises and, consequently, itsproperties would not be likely tochange as severely or as soon asmaterials having lower specificheat.

The differences involved maybe appreciated by comparingwidely different materials, forinstance:BRASS 0.0883 cals/gm/°CCORK 0.485 cals/gm/°CMARBLE 0.210 cals/gm/°CGLASS 0.199 cals/gm/°CNICKEL STEEL 0.109 cals/gm/°C

MACHINE OIL 0.400 cals/gm/°CPINEWOOD 0.670 cals/gm/°C

The various constituents that goto make up the structure of castiron have quite different specificheat values, for example:

150°C 850°CPURE IRON

(FERRITE) .121 .194 cals/gm/°CAUSTENITE .130 .159 cals/gm/°CCEMENTITE .149 .220 cals/gm/°CGRAPHITE .254 .454 cals/gm/°C

Actually, the specific heat ofthese materials will vary more asthe temperature changes thanthese figures would indicate.

For example, pure iron willshow a gradual increase to 750°Cand will then increase extremelyrapidly to a peak in the range of750 to 775°C, dropping downagain beyond 800°C.

Similarly, the specific heat ofgraphite changes quite rapidly asthe temperature rises, thus:

at 20°C 0.170 cals/gm/°Cat 138°C 0.254 cals/gm/°Cat 642°C 0.455 cals/gm/°Cat 896°C 0.454 cals/gm/°C

Values given for specific heatsof materials are usually the meanor average values over a giventemperature range.

As graphite has a differentvalue for specific heat than ferrite(iron) or cementite, it follows thatthe amount of graphite in thematrix and also its distributioncould have an effect on the overall

Specific Heat


ENGINEERING DATA

64

specific heat value. One wouldexpect a high carbon cast iron tohave a higher specific heat than alow carbon cast iron. Actually, thisis not so and, in fact, a highercarbon cast iron usually has alower specific heat than a lowcarbon cast iron. Some investiga-tors claim that below 500°C, thisposition is reversed.

Various types of Meehaniteshow the specific heat temperaturerelationship. (Figure 13)

It is also a fact that the amountof phosphorus has an influence onthe specific heat of a cast iron, forexample:.15% Phosphorus cast iron 0.118

cals/gm/°C.55% Phosphorus cast iron 0.104

cals/gm/°CPhosphorus, therefore, lowers thespecific heat of cast iron.

TYPEHR

TYPE HE

TYPE GC 40 (GC 275)

200

0.4

SP

EC

IFIC

HE

AT,

CA

LS

/GM

/°C

CENTIGRADE, 0°C

0.3

0.2

0.1

400 600 800 10000

Figure 13


ENGINEERING DATA

65

R

It is generally known thattemperatures below freezing tendto lower the strength and impactresistance of most metals.

Impact test results per sé can bevague and misleading because ofthe many variables in the testitself. Factors such as the type oftest bar, the temperature of testingand the method of applying theload are sometimes varied quiteindiscriminately. This has intro-duced an element of uncertainty inassessing test results.

Izod impact tests on a 0.798˝ (20 mm) diameter unnotched baron the flake graphite types ofMeehanite over a range oftemperatures from roomtemperature to -320°F (-196°C) are shown. (Figure 14)

The toughness of Types GM 60(GM 400) and GA 50 (GA 350)actually increased as the tempera-ture decreased to -320°F (-196°C)as at normal room temperature. Indesign, normal room temperatureimpact values may be used forthese metals.

When designing withMeehanite nodular irons whichare ductile for operation at sub-zero temperatures, it is necessaryto consider factors affecting the“transition temperature” of theiron. The transition temperature istemperature below which thematerial behaves in a brittle wayand exhibits a different appearingfracture. Above this temperature,the material behaves in a ductilemanner.

Sub-Zero Impact Properties

TYPE GM 60 (GM 400)

TYPE GA 50 (GA 350)

TYPE GC 40 (GC 275)

TYPE GE 30 (GE 200)

IZO

D I

MP

AC

T, f

t lb

f (N

.m)

TEMPERATURE °F/°C

+70+21

40(55.2)

30(41.4)

20(27.6)

10(13.8)

0-18

-70-57

-140-96

-210-134

-280-173

-350°F-212°C

Figure 14


ENGINGEERING DATA

66

In illustration Figure 15, the darkfractures are typically ductilewhereas the lighter fractureswhich have been tested at a lowertemperature exhibit the typicalappearance of a brittle fracture.

In dealing with the more ductilematerials, the chemistry as well asthe metallurgical structurebecomes important in determiningthe impact strength and thetransition temperature. Therefore,in applications where toughness isa factor, a material is chosenwhose transition temperatureoccurs below its normal operatingtemperature.

In the Meehanite nodular irons,Type SF 60 (SF 400) is designed tomaintain its toughness even downto sub-zero temperatures.

Types SP 80 (SP 600) and SH100 (SH 700) are primarilydesigned for high strength, andtheir toughness characteristics donot suit them for sub-zeroapplications with high shockloadings; however, they can beused in sub-zero applicationswhere high strength is requiredbut there is no shock loading.

Figure 16 shows transition

temperature tests for SF 60 (SF400). Tests are conducted on anotched bar. With the normalcomposition for average use as inCurve 3, the transition tempera-ture occurs at about 40°F (4.4°C).Where chemistry is suitablyaltered, as in the curve markedNo. 2, the transition temperaturemay be lowered about -30°F (-34°C).

Special heat treatments can alsobe used to further lower thetransition temperature of SF 60 (SF 400) to about -80°F (-62°C), as in Curve 1.

The heat treatment in this caseconsisted of heating to 1300°F(704°C), holding for 1⁄2 hour andwater quenching, then reheatingto 400°F (204°C) and holding attemperature for 24 hours. Thisheat treatment not only lowers thetransition temperature, but alsoraises the impact strength.

The lesson to be learned fromthese comparisons is that materi-als, such as nodular iron, whichare supposed to have good tough-ness, may exhibit severe brittle-ness if there composition is notrelated to service temperature.

Figure 15


ENGINGEERING DATA

67

R

Nodular iron castings havingthe silicon a little too high havebeen known to fracture with alight blow on a cold day, althoughtests taken from the same metalwere well above specification andexhibited normal ductility values.

When a design engineerdesigns for impact or shockresistance and he does not get it,the result may be catastrophic. Onthe other hand, the flake graphite

General Engineering irons whichare not ductile to start with behavein a very rational and predictablemanner in low temperatureservice.

While due allowance in designmust be made for the fact thatthey do not offer a high degree ofshock resistance, they can beexpected to conform to designconditions even at abnormally lowtemperatures.

Low SiliconSpecial Treatment

Normal Composition

*SF 60 (SF 400)

Low Silicon

*3*2

*1

TEMPERATURE °F/°C

-60-51

50

40

30

20

10

0-100°F-73°C

-20-29

+20-6.7

+60+16

+100+38

Figure 16


ENGINEERING DATA

68

Damping capacity is that propertywhich permits a material to absorbvibrational stresses.

With Meehanite Metal, itscombination of high dampingcapacity and strength puts it in aunique position and supplies theMeehanite foundry with a veryvaluable sales tool.

In order to understand theprinciple of damping vibration,consider what would happen to atuning fork made of Type GE 30(GE 200) Meehanite: When struck,it would vibrate for a few secondsonly. A similar fork made of TypeGA 50 (GA 350) Meehanite wouldprobably vibrate for a secondlonger–one of a nodular typeperhaps another second longer.

A fork made of steel wouldvibrate five to eight times longerand one of aluminum abouttwelve times longer.

The high damping capacity ofMeehanite Metal is a result of itscontrolled metallurgical structure;i.e., random graphite distributionin a uniform matrix.

Although it is possible toexpress the damping capacity infairly precise terms of energy ofamplitude absorption, asdetermined in a laboratoryinvestigation, it is difficult to makeuse of this information in a quanti-tative manner.

Along with ductility andimpact resistance, damping

capacity helps to prevent stressesfrom getting out of control. Ofcourse, strength is also necessaryto control stresses and this iswhere the basic principles of theMeehanite Process are importantbecause the uniform distributionor graphite in Meehanite Metalenables it to maintain the highdamping characteristics of grayiron together with high tensilestrength.

To better understand the valueof damping capacity, consider theapplication of a crankshaft in acombustion motor.

If the crankshaft is made ofMeehanite Metal with highdamping capacity, then theamplitude of the vibrations causedby operation are more readily keptwithin the fatigue limit of thematerial.

If the same crankshaft weremade from a material of similarstrength, but with lower dampingproperties, then the stresses mightbuild up to exceed the fatiguelimit and ultimately cause failure.

Materials having high dampingvalues are able to be deformed toa higher degree than Hooke’s lawpredicts without being damaged.

While there are several methodsof measuring damping, all meth-ods involve applying a knownstress and then measuring thereduction in stress accompanyingone or more cycles of vibrations.

Damping Capacity


ENGINEERING DATA

69

R

A curve, such as that shown inFigure 17, is obtained from such a test.

It can be seen that as theapplied stress is increased, thenthe specific damping capacityincreases. The amount of appliedstress is just one factor that canchange the damping capacity of atype of Meehanite once it hassolidified with a defined graphitesize and distribution.

For example, heat treatment canbe used to alter the matrix andhence the damping capacity of a

particular type. Stress relieftreatments produce about a 20%reduction in damping capacity. On the other hand, annealing toproduce a fully ferritic structureincreases the damping capacity.The same is true of quenching toproduce martensite; however, asthe structure is tempered andquenching stresses reduced, theability to absorb vibration alsodecreases.

The damping capacity forvarious materials expressed as thepercent of energy dissipated on

MEEHANITE TYPE GE

MEEHANITE TYPE GA

0.23% CARBON STEEL

5,000 PSI

30

35

SP

EC

IFIC

DA

MP

ING

CA

PA

CIT

Y P

ER

CE

NT

N/mm2

MAXIMUM TORSIONAL FIBER STRESS

SPECIFIC DAMPING CAPACITYFOR MEEHANITE METAL & STEEL

35

10,000

69

15,000

103

20,000

138

25,000

172

25

20

15

10

5

Figure 17


ENGINEERING DATA

70

the first cycle is given in thefollowing Table VI.

Common gray iron also showsthe high damping characteristicsof Meehanite Metal; but unless italso shows the high strength ofMeehanite Metal, it cannot main-tain its damping efficiency at highstresses.

Take the example of a powerhammer frame which failed whenmade from common gray iron:Engineers would immediatelyrecommend increasing sections ofthe replacement casting, but a

Meehanite foundryman shouldknow that unless a metal with apearlitic matrix is used, little, ifany, advantage is gained becausethe heavier section and slowercooling rate would produce aweaker casting.

Meehanite Metal with itsvarious types makes it possible forthe design engineer to select for agiven strength an iron of highdamping capacity, and provides amuch wider range of choice in thisrespect than all other engineeringmaterials.

TABLE VIDAMPING CAPACITY

(Percent of Energy Dissipated on the First Cycle)TORSION TORSION20,000 psi 10,000 psi

(138 N/mm2) (69 N/mm2)Torsional Stress Load LoadSoft Gray Iron 40.0 28.21020 Carbon Steel 8.0 5.5Aluminum 42.0 29.4GF 20 (GF 150) 32.0 19.2GE 30 (GE 200) 28.0 16.3GC 40 (GC 275) 24.0 12.0GA 50 (GA 350) 21.0GM 60 (GM 400) 14.0SF 60 (SF 400) 12.0SP 80 (SP 600) 11.0SH 100 (SH 700) 11.0GE 30 (GE 200) Stress Relieved 26.0GA 50 (GA 350) Quenched 32.0GA 50 (GA 350) Q & T (370°C/700°F) 28.0


ENGINEERING DATA

71

R

CONDITION TIME MOVEMENTAS-CAST 28 Months 4 x 10-5˝/ft (3.33 x 10-3mm/m)

STRESS RELIEVED 20 Months 2 x 10-5˝/ft (1.66 x 10-3mm/m)

Maintenance of accuracy ofdimension in service is of firstimportance in most modernengineering components.

In measurements made at the

National Physical Laboratory, themovement of Meehanite Type 50(GA 350) samples was found to beas follows:

Dimensional Stability

While it is well realized thatMeehanite Metal is not producedprimarily for its magnetic proper-ties, and does not compare as suchto materials made specifically forthis purpose, cases arise when itforms part of a magnetic circuitand it is still important to befamiliar with its magneticproperties.

It is frequently necessary for theengineer to consider other factorssuch as (1) cost (2) machinability(3) ease of manufacturer and (4)damping capacity, and it may wellbe that he will choose Meehanitefor certain components carryingmagnetic flux in spite of its lessermagnetic properties.

An advantage of Meehaniteover ordinary cast iron lies in thefact that each type of MeehaniteMetal is made to definite chemicaland metallurgical properties and,therefore, each type has welldefined magnetic properties, whilecast iron covers a broad range of

chemistry and metallurgy givingthe engineer only vague magneticproperties limits unless hespecifies the material’s chemistryhimself.

It is somewhat easier to com-pare magnetic terms to electricalterms that are more familiar. Inmagnetism, flux (Maxwells) isanalogous to current, permeability(Gauss) analogous to conductivity,and magnetic field or force(Oersteds) analogous to voltage.

The most commonly used mag-netic properties are illustrated bymeans of the conventional magne-tization curve and hysteresis loop.(Figure 18)1. Field strength or magnetizing

force (Symbol H) is expressed asoersteds, gilberts/cm, ampereturns/cm or ampere turns/inch.

2. Saturation intensity (gauss) isthe value of flux density (B)when saturation is reached(point A).

Magnetic Properties


3. Permeability (µ) (gauss) is theratio of B to H at any point onthe magnetization curve OA. It is quite common to quote val-ues of B for particular values of H (magnetizing force). Itsvalue is unity for air or other nonmagnetic media.

4. Remanence (gauss) is the fluxdensity remaining after satura-tion and removal of the appliedfield (value = line OC).

5. Coercive force (oersteds) is the field strength required todemagnetize after saturation(value = line OD).

6. Hysteresis loss (ergs/cc/cycle)is the energy lost and dissipatedas heat through one cycle, and isproportional to the area of theloop = area in gauss x oersteds/8π. It is more commonlyexpressed as watts/lb at 50 or

60 cycles for a given fluxdensity, usually 10,000 gauss.

7. Flux (maxwell or line) is thetotal quantity of magnetism in acircuit.

8. Flux density (gauss ormaxwell/sq. in) (Symbol B) isthe induction of magneticintensity.

Conversion and interrelation ofmagnetic units is as follows:

1 2.541 oersted = –––– a.t/cm = –––– a.t/inch0.4π 0.4π

field in oersteds = 0.4π field in a.t./cm =0.4π field in a.t./in2.54

1 gauss = 6.45 lines/sq. in

flux density influx density in gauss = lines/sq. in

6.451 gauss = 1 maxwell/sq. in = 1 maxwell/sq. cm1 oersted = 1 gilbert/centimeter

ENGINEERING DATA

72

F

B

E

D

C

H

A

O

Figure 18


ENGINEERING DATA

73

R

TABLE VIIFlux Density at Varying B (lines/sq. in) Coercive Hysteresis

MAX. Magnetizing Force H-oersteds at Remanence Force ergs/cc/watts/lbPERM 10 20 50 100 200 40 at/in 100 at/in (gauss) (oersted) Cycle at 60

GA 50 as-cast 300 2200 4800 8000 10000 12000 31000 51000 5400 15 26000 9GA 50 annealed 550 5250 7100 9000 10500 12500 45500 58000 6500 4-7 12000 4GA 50 quenched 80 400 1000 7000 9000 9500 6500 44500 5900 50 6000 20GA 50 quenched

& 275 1200 5000 8200 10250 12200 32000 53000 7000 18 30000 10tempered

GC 40 as-cast 220 1600 4300 7500 9500 10000 27700 48500 5100 12.5 24000 8GC 40 annealed 500 5000 7000 9000 10500 11000 45000 58000 5000 4-7 9000 3GE 30 as-cast 200 1600 4000 6900 9000 9600 25800 44500 4700 12 22000 7GE 30 annealed 400 4000 5600 7500 9200 9900 36000 48500 5000 4-6 9000 3SP 80 1450 7500 9100 11500 13500 15000 58500 74000 3600 2.0 7000SF 60 425 4200 7000 10200 12700 14000 45000 66000 6000 7.5 28000


ENGINEERING DATA

74

The machinability of MeehaniteMetal castings is one of their mostvaluable properties and theMeehanite organization is activelyengaged in devising ways to help-ing machine shops to obtain theutmost benefit from this property.

It is recognized that machinabil-

ity ratings are of little value with-out information on the practicaldetails of the machining operation.Emphasis, therefore, is being laidon the provision of the bestcombination of speed, feed, depthof cut, etc., for the different typesof Meehanite.

Machinability and Machining

Tool shapes for roughing cuts,based on the use of High Speed

Steel and on Cemented CarbideTools, are given above. (Figure 19)

Machining Practice and Tool Design

TABLE VIIIHIGH SPEED STEEL TOOLS TUNGSTEN CARBIDE TOOLS

Tool Angle Boring BoringLathe Planer Mill Lathe Planer Mill

Side cuttingedge angle 6°-10° 8°-10° 6°-10° 8°-10° 5°-10° 6°-10°

End cuttingedge angle 8°-12° 8°-12° 5°-8° 8°-10° 8°-10° 10°-12°

Front clearanceangle 2°-4° 2°-4° 4°-6° 4°-6° 4°-6° 2°-6°

Side clearanceangle 2°-5° 2°-5° 2°-8° 4°-6° 4°-6° 4°-6°

Back rake angle 4°-8° 3°-5° 0°-4° 0°-4° 0°-8° 0°-2°Side rake angle 6°-10° 6°-10° 6°-8° 2°-6° 2°-6° 2°-10°Nose radius 3.2-6.4mm 6.4mm 3.2-4.8 mm 3.2 mm 3.2 mm 0.8-6.4mm

1/8-1/4˝ 1/4˝ 1/8-3/16˝ 1/8˝ 1/8˝ 1/32-1/4˝

A

A

FrontClearance

Angle

NoseRadius

Section A-A

Side RakeAngle

BackRakeAngle

End Cutting EdgeAngle

Width

Side CuttingEdge Angle

Height

BaseSideClearanceAngle

Figure 19


ENGINEERING DATA

75

R

The recommended machiningpractice (turning, boring and

milling) using carbide tools isgiven below:

Coolants: Many castings may bemachined dry except for tappingand threading. Increased produc-tion is obtained by using estab-lished water soluble cutting

compounds that have a highwetting and dispersing quality.

Meehanite castings may also bemachined with high speed steel,or cast form cutters.

TABLE IXTURNING ROUGHING CUT FINISHING CUT

Type Speed Feed Speed FeedMeehanite s.f.m. in/rev s.f.m. in/rev

Metal (m/min) (mm/rev) (m/min) (mm/rev)GM-GA-SP 150-200 0.020-0.030 200-300 0.008-0.020

(46-61) (0.508-0.762) (61-91) (0.203-0.508)GC 200-250 0.020-0.030 250-350 0.008-0.020

(61-76) (0.506-0.762) (76-107) (0.203-0.508)GE-HE-SF 200-360 0.020-0.030 250-450 0.008-0.020

(61-110) (0.506-0.762) (76-137) (0.203-0.508)

BORING ROUGHING CUT FINISHING CUTType Speed Feed Speed Feed

Meehanite s.f.m. in/rev s.f.m. in/revMetal (m/min) (mm/rev) (m/min) (mm/rev)

GM-GA-SP 120-400 0.010-0.020 160-200 0.010-0.020(37-122) (0.254-0.508) (49-61) (0.254-0.508)

GC 180-240 0.010-0.022 200-250 0.010-0.020(55-73) (0.254-0.559) (61-76) (0.254-0.508)

GE-HE-SF 200-250 0.015-0.025 250-300 0.010-0.020(61-76) (0.381-0.635 (76-91) (0.254-0.508)

MILLING ROUGHING CUT FINISHING CUTType Speed Feed Speed Feed

Meehanite s.f.m. in/rev s.f.m. in/revMetal (m/min) (mm/rev) (m/min) (mm/rev)

GM-GA-SP 150-200 0.008-020 150-250 0.008-0.025(46-61) (0.203-0.508) (46-76) (0.203-0.635)

GC 180-200 0.008-0.022 180-275 0.008-0.030(55-61) (0.203-0.559) (55-84) (0.203-0.762)

GE-HE-SF 200-300 0.008-0.025 250-400 (0.008-0.030)(61-91) (0.203-0.635) (76-122) (0.203-0.762)


ENGINEERING DATA

76

The best cutting efficiency isobtained by using high feed andadjusting speed to the maximumtool life desired.

The speed-feed relationship forthe engineering types of

Meehanite Metal GA 50 (GA 350),GM 60 (GM 400), SP 80 (SP 600) aswell as for the softer types GC 40(GC 275), GE 30 (GE 200) and SF60 (SF 400) are charted in Figure20, based on actual turning tests.

Speed Feed Relationship

Dull tools cost money and wastetime. Correct angles, rakes andclearance are vital to efficientmetal removal. Grinding of toolsmust be exact. This requires use offixtures and competent toolgrinders. Hand grinding isundesirable.

Avoid water quenching ofcutters after grinding. This causesminute edge cracking and prema-ture failure in operation.

Use grinding-cutters entirelydry or under a wheel with amplewater directed on the cutter.

Avoid forcing cutters against agrinding wheel. This overheatsand burns the cutting edge of thetool causing flaking duringmachining operations.

Check all cutter angles with acutter grinding gauge.

Preparation and Sharpening of Tools

CODEX=MEEHANITE TYPE GM, GA & SPY=MEEHANITE TYPES GC, GE & SF

YX

0.010

500

SP

EE

D, S

.F.M

.

150

m/m

in

FEED, in/rev

SPEED-FEED RELATIONSHIP

400 120

300 90

200 60

100 30

0.020 0.030

0.254 0.508mm/rev

0

Figure 20


ENGINEERING DATA

77

R

Do not skimp in finish limits. Thequality of the surface of a castingis usually better on the bottomface of the casting. Therefore,design the pattern so that theimportant surface may be in themost favorable casting position.

Complicated and large castingsrequire wide tolerance limits.Castings having large flat areasrequire extra finish 3⁄8˝-1⁄2˝ (9.5 mm-12.7 mm) on top face,while 1⁄8˝ (3.1 mm) may be enough

on bottom face. If only one facemust be perfect, top limits may bereduced.

Before commencing machining,lay out machine surface at smallend or side of casting with draft toassure “clean-up” on all surfaces.

Castings may not clean up onall surfaces if the casting draft isnot taken into account. Machiningallowances involve manyvariables. Consult foundry.

Machining Allowances

Meehanite adapter ring for atomic reactor.


ENGINEERING DATA

78

Rolling Friction Type of WearSuch components as gears,sprockets, clutch plates, sheaves,trunnions, wheels, worm screws,ball races, cable drums, tires androllers, etc., all involve wearresistance in terms of surfacebehavior as a result of frictionwith or without shock, heat orattrition.

The basic surface stress valuesprovide an index of resistance to

surface disintegration or surfacefatigue.

The basic bending strengthfactors provide an index ofstrength in terms of tool shape.

These tests provide compara-tive data showing the highresistance of Meehanite castings tofailure from bending stresses inboth the cast and heat treatedconditions and to resist surfacewear and disintegration.

Properties Not Measured by P.S.I. Values

BY THE DAVID BROWN TESTTABLE X

BASIC SURFACE STRESS FACTORMeehanite Type GM 60 “as-cast” 1,600 (11.0)Meehanite Type GM 60 Heat Treated 400-500 BHN 2,400 (16.6)Meehanite Type GA 50 “as-cast” 1,450 (10.0)Meehanite Type GC 40 “as-cast” 1,400 (9.7)Meehanite Type SP 80 “as-cast” 1,800 (12.4)Meehanite Type SP 80 Heat Treated 340 BHN 2,500 (17.2)Meehanite Type SH 100 “as-cast” 2,500 (17.2)Meehanite Type SH 100 Heat Treated 350 BHN 2,700 (18.5)Ord. Cast Iron “as-cast” 1,000 (6.9)Phosphor Bronze, Sand Cast 700 (4.8)Cast Steel (C 0.35) 1,400 (9.6)

BASIC BENDING STRESS FACTORMeehanite Type GM 60 “as-cast” 15,500 (106.9)Meehanite Type GM 60 Heat Treated 500 BHN 16,000 (110.3)Meehanite Type GM 60 heat Treated 400 BHN 17,500 (120.7)Meehanite Type GA 50 “as-cast” 15,000 (103.4)Meehanite Type GC 40 “as-cast” 14,000 (96.6)Meehanite Type SP 80 “as-cast” 19,000 (131.0)Meehanite Type SP 80 Heat Treated 340 BHN 30,000 (206.9)Meehanite Type SH 100 “as-cast” 22,000 (151.7)Ord. Cast Iron 5,800 (40.0)Phosphor Bronze 7,000 (48.3)Cast Steel (C 0.35) 14,000 (96.6)


ENGINEERING DATA

79

R

In the design of industrial machin-ery, it is impossible to avoid themating of two or more metallicsurfaces under conditions thatinvolve movement and somedegree of friction.

Under many conditions, thisfriction may exceed a critical valuecausing adherence. The tearingaction that results damages one orboth surfaces and is usuallyreferred to as galling.

Where it is severe enough tocause a welding, this is known asseizing. Pickup, scuffing andscoring represent various ramifica-tions of the same problem.

Metal surfaces are actuallyattracted to one another by thenatural tendency of atoms andmolecules to combine. As surfacemolecules are only bounded onthree sides, they exert a strongattraction towards similar surfacemolecules.

By conditioning the metal sothat an amorphous non-crystallinelayer known as the Beilby layeroccurs, it is possible to consider-ably reduce this molecularattraction and decrease the surfacefriction between moving parts.

The ability of a material to be so conditioned and any built-inlubricative properties it may haveplay a vital part in avoidinggalling action.

Meehanite Metal contains freegraphite, which gives a certain“built-in” protective feature whenmetal parts operate together for ashort time without lubrication.

This feature is well illustratedbelow by the friction torque thatresults when Meehanite slidesagainst Meehanite, compared towhen it slides against steel contain-ing no free graphite. (Figure 21)

Comparative tests run usingsteel as a rotating member and

Galling, Seizing and Pickup

Steel sliding on cast iron

Meehanite sliding on Meehanite

500 lb

12

FR

ICT

ION

TO

RQ

UE

, ft

lb

f

16.50

N.m

Load, lb/kg

RESISTANCE TO FRICTION

227 kg

10

8

6

4

2

0

13.75

11.00

8.25

5.49

2.75

01000

454

1500

681

2000

908

2500

1135

Figure 21


ENGINEERING DATA

80

increasing the working load in 100pounds (45.4 kg) increments untilseizing occurs show the propor-tionate galling values of thematerials listed below.

By far the most important factor

that is operative in any gallingproblem is the surface condition ofthe mating surface. The effect ofsurface finish as measured in aspecial series of tests is tabulatedbelow.

Material Seizing Load, kg (lb)Meehanite Type GA 50 (GA 350) 1300 (590)Meehanite Type GE 30 (GE 200) 1200 (545)Graphitic cast iron 1000 (454)Navy bronze 800 (363)

Surface Condition Finish, in x 10-6(mm x 10-6) Seizing Load, lb (kg)Machined 65 (1651) 1000 (454)Ground 12 (305) Did not seize at 2500 (1135)Lapped 8 (203) Did not seize at 2500 (1135)

The finer the surface finish, thecloser the surface is to having aBeilby layer. Consequently, therunning-in period needed todevelop such a layer becomesincreasingly more critical as theoriginal surface becomes rougher.

In general, a material having afinish of 12 micro-inches (305micro-mm) or less will not requirea careful “wearing-in” period.

“Wearing in” may be accomp-lished by running at light loads forshort periods of time, allowingadequate time for rest or recoverybetween the running periods. Thegraphical illustration shows howthe friction co-efficient varies with “running in”. The final low co-efficient indicates theproduction of a Beilby layer on the surface. (Figures 22, 23)

On the other hand, a part thathas been “superfinished” at a

heavy load, as shown above, maybe regarded as being in the “run-in” condition because itexhibits a low frictional co-efficient right from the start.

Heat treatment of MeehaniteMetal followed by honing gives asurface that is virtually gall resis-tant. Additionally, the hardeningtreatment will result in excellentwear resistant characteristics.

Lubrication is obviously impor-tant in any metal to metal contact.Meehanite with its “built-in” lubri-cant in the form of graphite, is lesscritical in this regard. Be sure thatlubrication is adequate and thatonly the best lubricants are used.

Metals of high density (specifygravity 7.15 to 7.4) and with auniform distribution of graphite in an all pearlitic matrix, or in asorbitic matrix, offer the ultimatein galling resistance.


ENGINEERING DATA

81

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Avoid the use of castings thatexhibit excessive variation ofBrinell hardness across a surfaceor from section to section. It isquite likely that such castings will

not possess the best structure toresist galling where the conditionsof service are such that galling is aproblem.

181 kg (400 lb) load cycle

454 kg(100 lb) no galling

45 min. rest period

CO

-EF

FIC

IEN

T O

F F

RIC

TIO

N

MACHINED STEEL SLIDING ON MEEHANITE

227 kg

500 lbLoad, lb/kg

454

1000

681

1500

908

2000

1135

2500

0.3

0.1

0

6.8 kg(15 lb) load

seized

45.4 kg(100 lb) load

CO

-EF

FIC

IEN

T O

F F

RIC

TIO

N

SUPERFINISHED STEEL SLIDING ON MEEHANITE

227 kg

500 lbLoad, lb/kg

454

1000

681

1500

908

2000

1135

25000

0.2

0.1

Figure 22

Figure 23


ENGINEERING DATA

82

Meehanite Types SP 80 (SP 600),GM 60 (GM 400) and GA 50 (GA350) respond to heat treatment inthe same way as Carbon Steels. Byproper treatment, improvedtoughness and/or hardness mayreadily be obtained.

The effect of heat treatment onthe tensile strength and hardnessis illustrated in Figure 24 for TypeGA 50 (GA 350) Meehanite.

It will be noted that hardness isnot influenced by tempering attemperatures up to 400°F (204°C);therefore, when full hardness isrequired in a casting, temperingtreatment at this temperature isrecommended to remove harden-ing stresses. Maximum combinedtoughness and strength are

obtained by tempering in therange 716°F (379°C) to 806°F(430°C).

Where improved wearingproperties are required butmachining is necessary, temperingin the range 1000°F (538°C) to1100°F (593°C) will give Brinellhardness figures around 280 to 300.

Where hardness is required incombination with improvedtoughness, this may be obtainedby quenching from above thecritical temperature direct into amolten lead or salt bath at 500°F(260°C) to 720°F (382°C) where itshould remain one or more hours,according to the degree ofhardness or toughness desired.

Heat Treatment Data

The effect of quench and draw treatment on the impact strength and hardness of Type GA 50 (GA 350) Meehanite is portrayed above.

80,000(551.7)

TE

NS

ILE

, psi

(N

/mm

2)

BHN

HARDENED AND DRAWN AT °F/°C

100°F

38°C

300

149

500

260

700

371

900

482

1100

593

70,000(482.8)

60,000(413.8)

50,000(344.8)

40,000(275.9)

30,000(206.9)

20,000(138.0)

10,000(69.0)

0

CHARPYIMPACT

500

400

300

200

100

0

10 13.5

8 10.8

6 8.1

4 5.4

2 2.7

0 0.0

ftlbf N.m

AS CAST

Figure 24


ENGINEERING DATA

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Preheat the casting to 1100°F(593°C). Raise the temperature to1575°F (858°C) to 1600°F (871°C) asquickly as possible. When the cast-ing temperature blends with the fur-nace, quench in oil or water accord-ing to the degree of hardness re-quired. Withdraw from the quench-ing bath while warm–above 300°F)149°C)–and temper immediately.

The quenching medium used;i.e., oil, cold or warm water, shouldbe modified according to the

complexity of the casting to avoidoverstress causing cracking.

To temper hardened castings toremove stresses without losing anyhardness, reheat in oil at 400°F(204°C) for 1 to 2 hours per inch (0.4 to 0.8 hour per cm) of castingthickness.

Small castings in Meehanite TypeGC 40 (GC 275) also respond to heattreatment, but all castings to be sotreated should be specified on thecastings order.

General Heat Treatment Instructions

MachinabilityThere are two kinds of annealing for the purpose of improvedmachinability:Low Temperature Anneal–Improves machinability withoutmarkedly affecting the hardness, butmay cause about ten percent loss instrength properties.High Temperature Anneal–May cause loss of both strength andhardness to a marked extent ifannealing time is excessive. In thecase of high temperature annealing,which involves heating through thecritical range, it is recommendedpractice to heat slowly to 1200°F(648°C) and allow to soak at thistemperature.

The casting may then betransferred to another furnace which

has been previously heated to fullannealing temperature or else thetemperature of the preheating furnacemay be raised as quickly as possibleto the full annealing temperature.

This procedure is recommended toavoid excessive thermal shock withthe possible development of cracks inthe casting.

Table XI shows the recommendedtemperature for annealing forimproved machinability.

Heating time should not exceedone hour per inch of casting sectionfollowing by a slow cooling.

No Meehanite casting shouldrequire annealing for softening formachining purposes except inunusual cases, in which case thefoundry supplying the castingsshould be advised.

Annealing For Improved

TABLE VIIILow Temp. Anneal High Temp Anneal

Type °F (°C) °F (°C)GE 30 (GE 200) 1230/1260 (664/681) 1550 (842)GC 40 (GC 275) 1240/1280 (670/692) 1580 (860)GA 50 (GA 350) and

GM 60 (GM 400) 1250/1300 (675/704) 1600 (871)


ENGINEERING DATA

84

In the treatment of ferrous metals,it is possible to develop anunexpected degree of brittleness inan otherwise ductile material.

Basically, three types of brittle-ness may occur; viz., the ductile-brittle inversion which occurs atnear zero or sub-zero tempera-tures, brittleness that results ontempering or drawing a previouslyhardened part, and brittleness in aductile part resulting from slowcooling after the annealingtreatment.

There is some similaritybetween these three types ofbrittleness; and up to now, nocompletely satisfactory answer hasbeen found to this phenomenon.However, its existence has beenrecognized and means of avoidingit are being used.

In a flake graphite cast iron, thequestion of temper brittleness maybe ignored because the graphiteflakes themselves are so effectivein lowering toughness or impactstrength that the effect ofsecondary factors, such as temperembrittlement, is completelymasked.

In steels and in nodular castiron, however, care must be takenduring heat treatment to avoid thedevelopment of this unexpectedbrittleness.

In steels which may be consid-ered as closely parallel to nodularirons, temper embrittlement wasfirst observed on drawing backsteels, which had been hardenedby an oil quench treatment.

Figure 25 shows the change inIzod impact value with increasingtempering temperature.

In curve “B”, the sample isslowly cooled from each tempera-ture; whereas, in curve “A”, it israpidly cooled.

It is evident, therefore, that rapidcooling from the drawing tempera-ture produces higher toughness. Ithas been recognized that a steel maybe susceptible to temper embrittle-ment and a measure of susceptibilityhas been proposed.

The susceptibility ratio is thecomparison between the impactstrength after water quenching froma tempering of 1200°F (650°C) andthe impact strength after slowcooling from this temperature.

Alloys such as chromium,manganese, and phosphorusincrease susceptibility to temperbrittleness–carbon, nickel, silicon,and vanadium have little effectwhile molybdenum has a verymarked effect in preventing thisbrittleness. It has, therefore, becomea standard addition to steels whereembrittlement must be avoided.

In nodular cast irons where thestructure is ferritic, and where goodelongaton and impact strengths aredesired, this embrittlement also is animportant factor. It may occur inhardened nodular irons which aredrawn at temperatures ranging from840°F to 930°F (450°C to 500°C) or inductile nodular irons which areslowly cooled through this tempera-ture range after an annealingtreatment.

Temper Brittleness


ENGINEERING DATA

85

R

An iron quenched from 1200°F(650°C) is more ductile than onecooled slowly from this tempera-ture. Maximum ductility and thelowest impact transition tempera-ture will result when the sample iswater quenched from 1200°F(648°C) and then aged for 24 hoursat 400°F (204°C).

Embrittlement produced in aniron by tempering at 840°F (450°C)may be removed by quenchingfrom 1200°F (650°C).

The susceptibility of nodularirons to temper embrittlement is

increased by additions ofphosphorous and silicon, butphosphorus is more harmful thansilicon.

The addition of molybdenuminhibits embrittlement obtained inthe 843°F to 932°F (450°C to 500°C)range, providing that othercomposition factors such as siliconand phosphorus are normal.

Glavanizing embrittlementoccurs in irons which are galva-nized primarily because treatmentduring galvanizing involves heat-ing in the critical 843°F to 932°F

A

B

1200

IM

PA

CT

TO

UG

HN

ES

S,

ft l

bf

CHANGE IN IMPACT VALUEWITH INCREASING TEMPERATURE

70

100

8.2

N/m

m2

IMP

AC

T T

OU

GH

NE

SS

, N.m

80

60

50

40

30

20

10

0

TEMPERINGING TEMPERATURE, °C

200 300 400 500 600 700

95.9

109.6

82.2

68.5

54.8

41.1

27.4

13.7

0

Figure 25


ENGINEERING DATA

86

(450°C to 500°C) range duringimmersion in the galvanizing bath.

Galvanizing embrittlement maybe reduced or eliminated by a pre-quenching treatment from 1200°F(650°C) before the galvanizingtreatment. In addition to this, aminimum time in the galvanizingbath is desirable because embrittle-ment, in general, increases withthe time of exposure of the part in the embrittlement range.

While embrittlement may notnormally be a factor in producingcommercial nodular irons, it isimportant to recognize that it canoccur and, where impact strengthrequirements are important, it maynot be advisable to avoid thetemper embrittlement range bycooling rapidly from above thisrange and also to keep the compo-sition where the iron will be lesssusceptible to such embrittlement.

Where a casting is complex inform involving abrupt sectionchanges, internal stress may resultfrom varying cooling rates duringsolidification in the mold.

Annealing at a specific tempera-ture followed by slow cooling isthe correct scientific method ofremoving casting stress. The oldermethod of aging or weathering isrelatively useless (See Table XII).

The temperature and time ofannealing depend upon the typeof Meehanite used, the size of thecasting, and on the degree of stressrelief required.

Heating time should be suchthat no casting will be held at thespecified temperature longer thanis necessary to penetrate allsections uniformly. Castingsshould then be slowly cooled.

Stress Relieving

Meehanite castings may be weldedby means of the electric arc using asteel or alloy rod, or special castiron rod, or by gas, using cast iron,Meehanite or bronze rods.

It is recommended that in gaswelding, pre-heating of the casting

(or at least of the parts to be weld-ed) should be done to a dull redheat. Allow to cool slowly afterwelding.

For more information, refer toBulletin No. 59–WeldingMeehanite.

Welding

Table XII RECOMMENDED TEMPERATURES°F (°C)

Type GE 30 (GE 200) 950/1000 (510/538)Type GC 40 (GC 275) 1020/1070 (549/576)Type GA 50 (GA 350) and GM 60 (GM 400) 1080/1150 (582/620)


ENGINEERING DATA

87

R

Meehanite Metal is suitable for coating by welding highchromium alloys to the surface or by tinning, chrome-plating,

metal spraying, aluminizing orchromizing, etc., to increase itsresistance to heat and chemicalattack.

Coatings

Meehanite castings may be hardsurfaced by:

1. Chilling.2. Induction or flame

hardening.3. Welding hard alloy such as

stellite on the surface.Flame hardening is fundamen-

tally a simple process employingan oxy-acetylene flame directagainst the surface to be hardened.Rapid cooling is affected bycontact with a suitable quenchingmedium (usually water spray)immediately after heating.

The zone of maximum surfacehardness obtained with flame orinduction hardening is usuallyone-half to three-quarters of thetotal depth of the case and is file-hard.

Points to be remembered aboutcastings for flame hardening are:

1. Extra metal is desirable onlight castings to take care ofwarpage and ensure clean-upon machining.

2. Holes cause difficulty but, ifnecessary, should be counter-sunk and should not be toonear the edge of a casting.

3. Designs which involvesudden changes of light andheavy sections should beavoided.

4. If full hardness is desired onthe extreme ends of hardenedsurfaces, it must be specified.

5. Wall sections and ribsadjoining a hardened surfaceshould not be less than halfan inch thick.

Surface Hardening


The Meehanite Connection

88

Meehanite metal is a superior engi-neering cast iron, including nodularcast iron, flake graphite cast iron andwhite cast iron. It is made to exact andwell-defined engineering specifica-tions and, in the minds of experiencedcasting buyers, represents quality anddependability. Each type of Meehanitemetal has a definite identity, but whatis perhaps more important is that anycast iron specification can be pro-duced by the Meehanite process, andcan probably be made better by thisprocess than by any other procedure.Now, the Meehanite process is beingapplied very successfully to the man-ufacture of steel castings.There is no question about the engi-neering acceptability of Meehanitecastings and there can be very littlequestion about the relative merit ofthe Meehanite process. Consider onlythe fact that there are now over twohundred Meehanite licenseesthroughout the world and that closeto fifty of these licensees have beenusing the Meehanite process for overtwenty-five years, while about onehundred have been using it for morethan ten years. To them, at least, itmust be a worthwhile proposition.This is an association of progressivefoundries that is very much alive andup-to-date. In over 75 years of doingbusiness, the Meehanite MetalCorporation has been granted seventythree United States patents relating tofoundry methods and foundry tech-nology. Today, it has many new devel-opments on file, and we continue tolead the way in progressive foundrytechniques. Suppose now we considerexactly what happens when you takeout a Meehanite license so that youcan understand just how we operate,and you can then evaluate what ourservices might mean to you in thelong run. It should be emphasized

that this is no “get rich quick deal”!This is a carefully planned, gradualapproach to the overall improvementof your operations – one that will sur-vive the test of time, and one that willleave you with a better foundry, mak-ing better castings at a better profit!Plan of ActionThe first step is a careful analysis ofyour operations. This is followed by aplan of action for systematic correc-tion of your practice at a pace that youcan keep up with, and in such a waythat you do not experience any costlydelays or any major upset of yourestablished routine. When the overallplan has been decided and agreedupon, we begin the procedure ofimplementing it and gradual conver-sion to the Meehanite process. We arenot talking only about your metal oryour sand control – we are talkingabout every single facet of youroperation, including that oft neglectedarea of casting sales. This is acomplete package leading to overallquality improvement.Metal ControlWe usually begin with the metal andmelting; we show you where it couldbe improved, and we teach yourpeople by on-the-spot demonstration,by lectures and by the use of trainingcourses which will ensure a standardof competency in your key employ-ees. We establish a quality controlprocedure that will give you day-to-day consistency of operation at a highlevel of quality. Remember that thereis no single individual in yourfoundry who has our combinedexperience in the melting and process-ing of molten metal, and we havebeen able to successfully pass on thisexperience in foundries all over theworld, operating under a great varietyof conditions.

THE MEEHANITE CONNECTION

R


The Meehanite Connection

89

R

Gating and Risering We then usually proceed to gating andrisering practice, sand practice, mold-ing practice and all of the technologi-cal phases of foundry operations. Theexact sequence of installation will begoverned by your needs, and by theextent of your problems. Havinginstalled the process in hundreds offoundries, we know what to do andwhen to do it.StandardizationAll of the operations of the Meehaniteprocess are standardized in that theyfollow definite principles. Our techni-cal instruction books containing thesestandards are well-written and areclear and concise regarding the techni-cal details of the process. We will pro-vide you with standardized methodsfor all operations and will set up con-trol limits and a testing program tomaintain a very high standard ofquality in your product.Quality Management Traning (ISO 9000)Not only can Meehanite provide thecasting technology but we are alsoexperienced at training to the newquality system standards includingISO 9000, Ford Q1, and so on.We have our own quality programwhich we call the MeehaniteAcceptance Criteria, which, whenachieved, will meet all the require-ments of ISO 9000, but contains muchmore emphasis on continuousimprovement, which as we all realize,is the only road to survival. We pro-vide complete guidance, and all thedocumentation necessary. We train inthe use of statistics and other manage-ment techniques designed to improvequality and solve problems. Our train-ingmeans implementation of the qual-ity program, without additional staff.We are probably the only group ofexperienced professional foundry

engineers who are also experience notonly in training to the ISO standards,but also experienced in operatingunder this and similar quality sys-tems. We provide very practicaldown-to-earth guidance, which willlead you to, and through ISO 9000 cer-tification.Technology TrainingA license will provide you with theadvantages of training your people inbetter methods and procedures imple-mented with written instructions onall phases of your operation. It willprovide lectures and discussion onany foundry subject, and a technolog-ical training program is available to beused at home by your key people, sothat their knowledge may beincreased, and so that the quality oftheir performance in their daily taskswill be enhanced. Standardization ofnormal operations will allow themmore time to devote to a continuousimprovement of your product both inquality and in reduced cost of manu-facture. It is only a group effort, astypified by the Meehanite organiza-tion, that makes such a program avail-able even to the relatively smallfoundry operations.S.P.C. TRAININGMeehanite has years of experience inthe use of S.P.C. and we have definiteprograms for dealing with S.P.C. inthe jobbing foundry environment. Wewill train your personnel.The efficient use of S.P.C. whenapplied correctly can be the basis fordeveloping effective continuousimprovement programs. We will helpyou implement and integrate S.P.C.into your quality system, so that youreceive the most benefit from thistechnology.


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