HEAT TREATMENT OF TOOL STEEL

SS-EN ISO 9001SS-EN ISO 14001

ContentsWhat is tool steel? .................................... 3

Hardening and tempering ......................... 3

Dimensional and shape stability ............... 7

Surface treatment ..................................... 8

Testing of mechanical properties .............. 10

Some words of advice to tool designers ... 11

This information is based on our present state of knowledge and is intended to provide generalnotes on our products and their uses. It should not therefore be construed as a warranty ofspecific properties of the products described or a warranty for fitness for a particular purpose.

Classified according to EU Directive 1999/45/ECFor further information see our “Material Safety Data Sheets”.

Edition 6, 12.2007The latest revised edition of this brochure is the English version,which is always published on our web site www.uddeholm.com

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The purpose of this brochure is to pro-vide some idea of how tool steel is heattreated and how it behaves.

Special attention is paid to hardness,toughness and dimensional stability.

= Possible positions for carbonatoms

= Iron atoms

3,57 A

2,85 A

2.98 A

2,86 A

Unit cell in a martensite crystal

Unit cell in an austenite crystalFace centred cubic (FCC)

Unit cell in a ferrite crystalBody centred cubic (BCC)

What is tool steel?Uddeholm has concentrated its toolsteel range on high alloyed types ofsteel, intended primarily for purposessuch as plastics moulding, blanking andforming, die casting, extrusion, forgingand wood-working.

Conventional high speed steels andpowder metallurgy (PM) steels are alsoincluded in the range.

Tool steel is normally delivered in thesoft annealed condition. This is to makethe material easy to machine with cutt-ing tools and to give it a microstructuresuitable for hardening.

The microstructure consists of a softmatrix in which carbides are embedded.In carbon steel, these carbides consist ofiron carbide, while in the alloyed steelthey are chromium (Cr), tungsten (W),molybdenum (Mo) or vanadium (V)carbides, depending on the compositionof the steel. Carbides are compounds ofcarbon and these alloying elements andare characterized by very high hardness.A higher carbide content means higherresistance to wear.

In alloy steels, it is important that thecarbides are evenly distributed.

Other alloying elements are alsoused in tool steel, such as cobalt (Co)and nickel (Ni), but these do not formcarbides. Cobalt is normally used to im-prove red hardness in high speed steels,nickel to improve through-hardeningproperties.

Hardeningand temperingWhen a tool is hardened, many factorsinfluence the result.

SOME THEORETICAL ASPECTS

In soft annealed tool steel, most of thealloying elements are bound up withcarbon in carbides. In addition to thesethere are the alloying elements cobaltand nickel, which do not form carbidesbut are instead dissolved in the matrix.

When the steel is heated for harden-ing, the basic idea is to dissolve the car-bides to such a degree that the matrixacquires an alloying content that givesthe hardening effect—without becom-ing coarse grained and brittle.

Note that the carbides are partially dis-solved. This means that the matrix be-comes alloyed with carbon andcarbide-forming elements.

When the steel is heated to the hard-ening temperature (austenitizing tem-perature), the carbides are partially dis-solved, and the matrix is also altered. Itis transformed from ferrite to austenite.This means that the iron atoms changetheir position in the atomic lattice andmake room for atoms of carbon andalloying elements. The carbon and alloy-ing elements from the carbides are dis-solved in the matrix.

If the steel is quenched sufficientlyrapid in the hardening process, the car-bon atoms do not have time to reposi-tion themselves to allow the reformingof ferrite from austenite, i.e. as in an-nealing. Instead, they are fixed in posi-tions where they really do not haveenough room, and the result is highmicrostresses that can be defined as in-creased hardness. This hard structure iscalled martensite. Thus, martensite canbe seen as a forced solution of carbonin ferrite.

When a steel is hardened, the matrixis not completely converted into mar-tensite. Some austenite is always leftand is called “retained austenite”. Theamount increases with increasing alloy-ing content, higher hardening tempera-ture and longer soaking times.

After quenching, the steel has amicrostructure consisting of martensite,retained austenite and carbides. Thisstructure contains inherent stresses thatcan easily cause cracking. But this canbe prevented by reheating the steel to acertain temperature, reducing the stres-ses and transforming the retained aus-tenite to an extent that depends uponthe reheating temperature. This reheat-ing after hardening is called tempering.Hardening of a tool steel should alwaysbe followed immediately by tempering.

It should be noted that tempering atlow temperatures only affects the mar-tensite, while tempering at high tem-perature also affects the retained auste-nite.

After one tempering at high tem-perature, the microstructure consists oftempered martensite, newlyformedmartensite, some retained austenite andcarbides.

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Hardness

Tempering temperature

A = martensite temperingB = carbide precipitationC = transformation of retained austenite to

martensiteD = tempering diagram for high speed steel

and high alloy tool steelA+B+C = D

The diagram shows the influence of differentparameters on the secondary hardening.

A

D

BC

Tempered once.

Tempered twice. 1000x

Uddeholm Rigor, hardenedand tempered.

Salt bath furnace

Batch type furnacewith a controlled atmosphere

Vacuum furnace

HOW HARDENING AND TEMPERINGIS DONE IN PRACTICE

Distortion due to hardening must betaken into consideration when a tool isrough-machined. Rough machiningcauses local heating and mechanicalworking of the steel, which gives rise toinherent stresses. This is not serious ona symmetrical part of simple design, butcan be significant in asymmetricalmachining, for example of one half of adie casting die. Here, stress relieving isalways recommended.

Stress relieving

This treatment is done after roughmachining and entails heating to 550–650°C (1020–1200°F). The materialshould be heated until it has achieveduniform temperature all the waythrough and then cooled slowly, forexample in a furnace.

The idea behind stress relieving isthat the yield strength of the material atthe elevated temperature is so low thatthe material cannot resist the inherentstresses. The yield strength is exceededand these stresses are released, result-ing in a greater or lesser degree of dis-tortion.

The correct work sequence is:rough machining, stress relieving andsemifinish machining.

The excuse that stress relieving takestoo much time is hardly valid. Rectifyinga part during semifinish machining ofan annealed material is with few excep-tions cheaper than making dimensionaladjustments during finish machining ofa hardened tool.

Heating to hardening temperature

The fundamental rule for heating tohardening temperature is that it shouldtake place slowly. This minimizes distor-tion.

In vacuum furnaces and furnaceswith controlled protective gas atmos-phere, the heat is increased gradually.When molten salt baths are used, pre-heating is employed, whereas heating isautomatically slow in a muffle furnacewhen steel is packed in castiron chips.

In a fluidized bed the advantages ofsalt bath and protective atmosphere are

Tool steel should always be double-tempered. The second tempering takescare of the newly formed martensiteformed after the first tempering. Threetempers are recommended for highspeed steel with a high carbon content.

combined. Heating and cooling ratescan be compared with salt bath. TheAl-oxides and gas used as protectiveatmosphere are less detrimental to theenvironment than salt bath.

It is important that the tools areprotected against oxidation and decar-burization. The best protection is pro-vided by a vacuum furnace, where thesurface of the steel remains unaffected.

Furnaces with a controlled protectivegas atmosphere or salt baths also pro-vide good protection.

If an electric muffle furnace is used,the tool can be protected by packing itin spent charcoal or cast iron chips.

It should be observed that thesepacking materials can have a carburiz-ing effect if the steels have a low car-bon content, such as conventional hotwork steels.

Precipitated secondary (newly formed)carbides and newly formed martensitecan increase hardness during high-temperature tempering. Typical of this isthe so called secondary hardening ofe.g. high speed steel and high alloyedtool steels.

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in the microstructure can take place,risking a poor tool performance.

Water is used as a quenching me-dium for unalloyed steels. 8–10% so-dium chloride (salt) or soda should beadded to the water in order to achieveoptimum cooling efficiency. Water hard-ening can often cause problems in theform of distortion and quench cracks.Oil hardening is safer, but hardening inair or martempering is best of all.

Oil should be used for low alloyedsteels. The oil should be of good quality,and preferably of the rapid quenchingtype. It should be kept clean and mustbe changed after a certain period of use.Hardening oils should have a tempera-ture of 50–70°C (140–160°F) to givethe best cooling efficiency. Lower tem-peratures mean higher viscosity, i.e. theoil is thicker.

Hardening in oil is not the safest wayto quench steel, in view of the risks ofdistortion and hardening cracks. Theserisks can be reduced by means of mar-tempering. In this process, the materialis quenched in two steps. First it iscooled from hardening temperature in asalt bath whose temperature is justabove the MS temperature. It is keptthere until the temperature has equal-ized between the surface and the core,after which the tool can be allowed tocool freely in air down through themartensite transformation range.

When martempering oil hardeningsteels, it should also be kept in mindthat the material transforms relativelyrapid and should not be kept too long atthe martempering bath temperature.This can lead to excessive bainite trans-formation and the risk of low hardness.

High alloy steels can be hardened inoil, a martempering bath or air. Theadvantages and disadvantages of thedifferent methods can be discussed.

Oil gives a good finish and highhardness, but it also maximizes the riskof excessive distortion or cracking. Inthe case of thick parts, quenching in oilis often the only way to achieve maxi-mum hardness.

Martempering in salt bath producesa good finish, high hardness and lessrisk of excessive distortion or cracking.For certain types of steel, the tempera-

The quenching process as expressed in aTTT graph

Martensite

Core

AC1

AC3

Temperature

Surface

MS

Martempering

AC1

AC3

Temperature

Core

MS

Martensite

Time

Surface

ture of the salt bath is normally kept atabout 500°C (930°F). This temperatureensures a relatively mild thermal shock,but a sufficient cooling rate to avoidphase transformations.

Full martensite transformation has,in many cases, time to occur when thesteel is cooled in air from the martem-pering bath temperature. However, ifthe dimensions are big, it is often nec-essary to use a forced quenching ratedepending of the hardenability of thesteel.

Holding time athardening temperature

It is not possible to state exact recom-mendations briefly to cover all heatingsituations.

Factors such as furnace type, furnacerating, temperature level, the weight ofthe charge in relation to the size of thefurnace etc., must be taken into consid-eration in each case.

We can, however, give one recom-mendation that is valid in virtually allsituations:• when the steel has reached hardening

temperature through its entire thick-ness, hold at this temperature for30 minutes. An exception to this ruleis for thin parts heated in salt baths athigh temperature, or high speed steel.Here the entire period of immersion isoften only a few minutes.

Quenching

The choice between a fast and slowquenching rate is usually a compromise;to get the best microstructure and toolperformance, the quenching rate shouldbe rapid; to minimize distortion, a slowquenching rate is recommended.

Slow quenching results in less tem-perature difference between the surfaceand core of a part, and sections of dif-ferent thickness will have a more uni-form cooling rate.

This is of great importance whenquenching through the martensiterange, below the Ms temperature. Mar-tensite formation leads to an increase involume and stresses in the material. Thisis also the reason why quenchingshould be interrupted before room tem-perature has been reached, normally at50–70°C (120–160°F).

However, if the quenching rate is tooslow, especially with heavier cross-sections, undersirable transformations

Wrapping in stainless steel foil alsoprovides good protection when heatingin a muffle furnace.

Decarburization results in low sur-face hardness and a risk of cracking.

Carburization results in a hardersurface layer, which can have negativeeffects.

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Air quenching entails the least risk ofexcessive distortion. A tendency to-wards lower hardness is noticeable atgreater thicknesses. One disadvantageis a poorer finish.

Some oxidation takes place when thematerial comes into contact with airand cools slowly from the high harden-ing temperatures.

The choice of quenching mediummust be made from job to job, but ageneral recommendation could perhapsbe made as follows:

TimeCooling rates for various media

MS

Hardening temperature

Room temperature

SurfaceOil

Temperature

Air

Convection typetempering furnace

Salt bath

Core

Tempering

The material should be tempered imme-diately after quenching. Quenchingshould be stopped at a temperature of50–70°C (120–160°F) and temperingshould be done at once. If this is notpossible, the material must be keptwarm, e.g. in a special “hot cabinet”,awaiting tempering.

The choice of tempering temperatureis often determined by experience. How-ever, certain guidelines can be drawnand the following factors can be takeninto consideration:• hardness• toughness• dimension change.

If maximum hardness is desired, tem-per at about 200°C (390°F), but neverlower than 180°C (360°F). High speedsteel is normally tempered at about20°C (36°F) above the peak of the sec-ondary hardening temperature.

If a lower hardness is desired, thismeans a higher tempering temperature.Reduced hardness does not alwaysmean increased toughness, as is evidentfrom the toughness values in our pro-duct brochures. Avoid tempering withintemperature ranges that reduce tough-ness. If dimensional stability is also an

A martempering bath is the safest inmost cases.

Air is used when dimensional stabil-ity is crucial.

Oil should be avoided and used onlywhen it is necessary to achieve satisfac-tory hardness in heavy sections.

Three well known quenching meth-ods have been mentioned here. Somenew concepts have been introducedwith modern types of furnaces, and thetechnique of quenching at a controlledrate in a protective gas atmosphere orin a vacuum furnace with gas is becom-ing increasingly widespread. The coolingrate is roughly the same as in air forprotective gas atmosphere, but theproblem of oxidized surfaces is elimi-nated. Modern vacuum furnaces havethe possibility to use overpressureduring quenching which increases thequenching speed. The surfaces are com-pletely clean after a vacuum hardening,

With these techniques, as withquenching in air, the risks of excessivelyslow cooling must be borne in mind,even for vacuum furnaces if no over-pressure is used. The effect is that sur-face hardness is normally lower than

expected. Hardness in the centre ofheavy sections is even lower.

This effect can be critical with highspeed steel and hot work steel, where acentre section can be cooled so slowlythat carbide precipitation takes place onthe way down. Here, the matrix be-comes depleted of carbon and carbide-forming alloying elements. The result isreduced hardness and strength of thecore.

important consideration, the choice oftempering temperature must often be acompromise. If possible, however, prior-ity should be given to toughness.

How many tempers are required?

Two tempers are recommended for toolsteel and three are considered neces-sary for high speed steel with a highcarbon content, e.g. over 1%.

Two tempers are always recom-mended. If the basic rule in quenching isfollowed—to interrupt at 50–70°C(120–160°F)—then a certain amount ofaustenite remains untransformed whenthe material is to be tempered. Whenthe material cools after tempering, mostof the austenite is transformed to mar-tensite. It is untempered. A second tem-pering gives the material optimumtoughness at the hardness in question.

The same line of reasoning can beapplied with regard to retained auste-nite in high speed steel. In this case,however, the retained austenite is highlyalloyed and slow transforming. Duringtempering, some diffusion takes place inthe austenite, secondary carbides areprecipitated, the austenite becomeslower alloyed and is more easily trans-formed to martensite when it cools aftertempering. Here, several temperings canbe beneficial in driving the transforma-tion of the retained austenite further tomartensite.

Holding times in connectionwith tempering

Here also, one should avoid all compli-cated formulae and rules of thumb, andadopt the following recommendation:After the tool is heated through, holdthe material for at least 2 hours at fulltemperature each time.

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Yield strength Rp0,2MPa

400

300250200

100

Thermal stresses

These stresses are created when a pieceis heated. They increase if heating takesplace rapidly or unevenly. The volumeof the steel is increased by heating.Uneven heating can result in local varia-tions in volume growth, leading to stres-ses and distortion.

As an alternative with large or com-plex parts, heating can be done in pre-heating stages in order to equalize thetemperature in the component.

Linear expansion mm/100 mm

0,8

0,6

0,4

0,2

Effect of temperature on the linear expansionof Uddeholm ORVAR 2 Microdized, soft annealed

Dimensional andshape stabilityDISTORTION DURING THEHARDENING AND TEMPERING OFTOOL STEEL

When a piece of tool steel is hardenedand tempered, some warpage or distor-tion normally occurs. This distortion isusually greater at high temperature.

This is well known, and it is normalpractice to leave some machining allow-ance on the tool prior to hardening. Thismakes it possible to adjust the tool tothe correct dimensions after hardeningand tempering by grinding, for example.

How does distortion take place?

The cause is stresses in the material.These stresses can be divided into:• machining stresses• thermal stresses• transformation stresses.

Machining stresses

This type of stress is generated duringmachining operations such as turning,milling and grinding. (For example, suchstresses are formed to a greater extentduring cold forming operations such asblanking, bending and drawing.)

If stresses have built up in a part,they will be released during heating.Heating reduces strength, releasingstresses through local distortion. Thiscan lead to overall distortion.

In order to reduce this distortionwhile heating during the hardeningprocess, a stress relieving operation canbe carried out prior to the hardeningoperation. It is recommended that the

100 200 300 400 500 600°C

Temperature

100 200 300 400 500 600°C

Temperature

Effect of temperature on the yield strength ofUddeholm Orvar 2 Microdized, soft annealed

material be stress relieved after roughmachining. Any distorsion can then beadjusted during semifinish machiningprior to the hardening operation.

An attempt should always be madeto heat slowly enough so that the temperature remains virtually equalthroughout the piece.

What has been said regarding heat-ing also applies to quenching. Verypowerful stresses arise during quench-ing. As a general rule, the slower that

Transformationto austenite

Volume changes due to structuraltransformation

Volume

Ms AC1 AC3

Temperature

Trans-formationto martensite

quenching can be done, the less distor-tion will occur due to thermal stresses.

It is important that the quenchingmedium is applied as uniformly as pos-sible. This is especially valid whenforced air or protective gas atmosphere(as in vacuum furnaces) is used. Other-wise temperature differences in the toolcan lead to significant distortion.

Transformation stresses

This type of stress arises when themicrostructure of the steel is trans-formed. This is because the three micro-structures in question—ferrite, auste-nite and martensite—have differentdensities, i.e. volumes.

The greatest effect is caused bytransformation from austenite to mar-tensite. This causes a volume increase.

Excessively rapid and unevenquenching can also cause local marten-site formation and thereby volumeincreases locally in a piece and give riseto stresses in this section. These stressescan lead to distortion and, in somecases, quenching cracks.

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HOW CAN DISTORTIONBE REDUCED?

Distortion can be minimized by:• keeping the design simple and

symmetrical• eliminating machining stresses by

stress relieving after rough machining• heating slowly during hardening• using a suitable grade of steel• quenching the piece as slowly as

possible, but quick enough to obtaina correct microstructure in the steel

• tempering at a suitable temperature.

The following values for machiningallowances can be used as guidelines.

Machining allowanceGrade of steel on length and diameter

as % of dimension

UDDEHOLM ARNE 0,25 %UDDEHOLM RIGOR 0,20 %UDDEHOLM SVERKER 21 0,20 %UDDEHOLM SVERKER 3 0,20 %UDDEHOLM CARMO 0,20 %UDDEHOLM SLEIPNER 0,25 %UDDEHOLM CALDIE 0,25 %UDDEHOLM VANADIS 4 Extra 0,15 %UDDEHOLM VANADIS 6 0,15 %UDDEHOLM VANADIS 10 0,15 %UDDEHOLM VANADIS 23 0,15 %UDDEHOLM VANCRON 40 0,20 %UDDEHOLM CALMAX 0,20 %UDDEHOLM GRANE 0,15 %UDDEHOLM STAVAX ESR 0,15 %UDDEHOLM MIRRAX ESR 0,20 %UDDEHOLM ELMAX 0,15 %UDDEHOLM CORRAX 0,05–0,15 %UDDEHOLM ORVAR 2 Microdized 0,20 %UDDEHOLM ORVAR SUPREME 0,20 %UDDEHOLM VIDAR SUPERIOR 0,20 %UDDEHOLM QRO 90 SUPREME 0,30 %UDDEHOLM HOTVAR 0,40 %UDDEHOLM DIEVAR 0,30 %UDDEHOLM ROLTEC SF 0,15 %UDDEHOLM TOUGHTEC SF 0,15 %UDDEHOLM WEARTEC SF 0,15 %

Surface treatmentNITRIDING

The purpose of nitriding is to increasethe surface hardness of the steel andimprove its wear properties. This treat-ment takes place in a medium (gas orsalt) which gives off nitrogen. Duringnitriding, nitrogen diffuses into the steeland forms hard, wear resistant nitrides.This results in an intermetallic surfacelayer with good wearing and frictionalproperties.

NITROCARBURIZING

A widely known method is nitriding in asalt bath.

The temperature is normally 570°C(1060°F). Due to aeration the cyanatecontent of the bath can be better con-trolled and the nitriding effect is verygood.

A nitrocarburizing effect can also beachieved in gas atmosphere at 570°C(1060°F). The results after thesemethods are comparable.

The total nitriding time must be var-ied for different tool types and sizes. Inthe case of large sizes, the heating time

Nitrided case shown at a magnification of100X Uddeholm Orvar 2 Microdized

Note: Uddeholm Corrax is a precipita-tion hardening steel. Machining allow-ance is needed to compensate forshrinkage during ageing. The shrinkagedepends on ageing temperature (seeproduct information brochure). No dis-tortion occurs.

SUB-ZERO TREATMENT

Tools requiring maximum dimensionalstability in service can be sub-zerotreated as follows:

Immediately after quenching, thetool should be sub-zero treated to –70

Examples of applications

• Nitriding is used in some cases onprehardened plastic moulds in orderto prevent indentation and defects onthe parting faces. It should be noted,however, that a nitrided surface can-not be machined with cutting toolsand can only be ground with diffi-culty. A nitrided surface will causeproblems in weld repairing as well.Nitriding can also have a stress reliev-ing effect. Heavily machined partsmay, therefore, undergo some distor-tion during nitriding due to the re-lease of residual stresses from machi-ning and in such a case, a stress re-lieving between rough and finishmachining is recommended.

• The life of forging dies can be in-creased by nitriding. It must be noted,though, that the treatment can giverise to higher susceptibility to crack-ing in sharp corners. Furthermore, theedge of the flash land must be givena rounded profile.

• Extrusion dies of Uddeholm Orvar 2Microdized can be nitrided to advan-tage—especially in the case of alumi-nium alloys. Exceptions can be pro-files with sharp corners and thin sec-tions of the dies.

Nitriding is done in gas at about 510°C(950°F) and in salt or gas at about570°C (1060°F) or as ion nitriding,normally at around 500°C (930°F). Theprocess therefore requires steels thatare resistant to tempering in order notto reduce the core strength.

to –80°C (–95 to –110°F), soaking time1–3 hours, followed by tempering.

The sub-zero treatment leads to areduction of retained austenite content.This, in turn, will result in a hardnessincrease of 1–2 HRC in comparison tonot sub-zero treated tools if low tem-perature tempering is used. For hightemperature tempered tools there willbe little or no hardness increase andwhen referencing the normal temperingcurves, a 25 to 50°C (45 to 90°F) lowertempering temperature should be cho-sen to achieve the required hardness.

Tools that are high temperaturetempered, even without a sub-zerotreatment, will normally have a lowretained austenite content and in mostcases, a sufficient dimensional stability.However, for high demands on dimen-sional stability in service it is also rec-ommended to use a sub-zero treatmentin combination with high temperaturetempering.

For the highest requirements ondimensional stability, sub-zero treat-ment in liquid nitrogen is recommendedafter quenching and after each temper-ing.

HEAT TREATMENT

9

CASE HARDENING

In this method, the steel is heated in amedium that gives off carbon (gas, saltor dry carburizing compound). The car-bon diffuses into the surface of thematerial and after hardening this givesa surface layer with enhanced hardnessand wear resistance. This method isused for structural steel, but is not gen-erally recommended for alloy tool steels.

HARD CHROMIUM PLATING

Hard chromium plating can improve thewear resistance and corrosion resistanceof a tool. Hard chromium plating is doneelectrolytically. The thickness of theplating is normally between 0,001 and0,1 mm (0,00004–0,004 inch). It can bedifficult to obtain a uniform surfacelayer, especially on complex tools, sinceprojecting corners and edges may re-

Ion nitriding plant

SURFACE COATING

Surface coating of tool steel is becom-ing more common. Not only for coldwork applications, but also for plasticmoulds and hot work dies.

The hard coating normally consistsof titanium nitride and/or titaniumcarbide. The very high hardness and lowfriction gives a very wear resistantsurface, minimizing the risk for adhe-sion and sticking.

To be able to use these properties inan optimal way one has to choose atool steel of high quality or a powdermetallurgy manufactured steel as sub-strate. The two most common coatingmethods are:• PVD coating: performed at 200–

500°C (390–930°F) (PVD = PhysicalVapour Deposition).

• CVD coating: performed at about1000°C (1830°F) (CVD = ChemicalVapour Deposition).

Certain demands are put on the toolsteel depending on: coating method, thedesign of the tool and the tolerancesneeded. PVD coating is used for thehighest demands on tolerances. Whenusing this method a tool steel with hightempering resistance must be used andthe surface coating has to be performedas the last operation, after the heattreatment. At CVD coating, hardeningand tempering are done after the coat-ing. When using the CVD method thereis a risk for dimensional changes. Themethod is therefore not recommendedfor tools with requirements of verynarrow tolerances.

The most suitable steels for the men-tioned methods are Uddeholm Vanadis4 Extra, Uddeholm Vanadis 6, UddeholmVanadis 10, Uddeholm Vanadis 23 andUddeholm Caldie.

Surface coating of tools and mouldsshould be discussed from case to caseconsidering the application, coatingmethod and tolerance requirements .

Coated tools

ceive a thicker deposit than large flatsurfaces or the holes. If the chromiumlayer is damaged, the exposed steel maycorrode rapidly.

Another advantage of the chromiumlayer is that it greatly reduces the coeffi-cient of friction on the surface.

During the chromium plating process,hydrogen absorption can cause a brittlesurface layer. This nuisance can be elimi-nated by tempering immediately afterplating at 180°C (360°F) for 4 hours.

to the specified nitriding temperaturecan be considerably longer than in thecase of small tools.

ION NITRIDING

This is a new nitriding technology. Themethod can be summarized as follows:

The part to be nitrided is placed in aprocess chamber filled with gas, mainlynitrogen. The part forms the cathodeand the shell of the chamber the anodein an electric circuit. When the circuit isclosed, the gas is ionized and the part issubjected to ion bombardment. The gasserves both as heating and nitridingmedium.

The advantages of ion nitriding in-clude a low process temperature and ahard, tough surface layer. The depth ofdiffusion is of the same order as withgas nitriding.

HEAT TREATMENT

10

F0+F1=FF0 F0

h0 h e HRC

Surface of specimen

HRCh

h0

e

100

0

Hard

ness

sca

le

0,2 mm

D

F

d

h

Testingof mechanicalpropertiesWhen the steel is hardened and tem-pered, its strength is affected, so let ustake a closer look at how these proper-ties are measured.

HARDNESS TESTING

Hardness testing is the most popularway to check the results of hardening.Hardness is usually the property that isspecified when a tool is hardened.

It is easy to test hardness. The mate-rial is not destroyed and the apparatusis relatively inexpensive. The most com-mon methods are Rockwell C (HRC),Vickers (HV) and Brinell (HBW).

We shouldn’t entirely forget the oldexpression “file-hard”. In order to checkwhether hardness is satisfactory, forexample above 60 HRC, a file of goodquality can provide a good indication.

Rockwell (HRC)

In Rockwell hardness testing, a conicaldiamond is first pressed with a force F0,and then with a force F0+F1 against aspecimen of the material whose hard-ness is to be determined. After unload-ing to F0, the increase (e) of the depthof the impression caused by F1 is deter-mined. The depth of penetration (e) isconverted into a hardness number

Principle of Rockwell hardness testing

Brinell (HBW)

In Brinell hardness testing, a Tungsten(W) ball is pressed against the materialwhose hardness is to be determined.After unloading, two measurements ofthe diameter of the impression aretaken at 90° to each other (d1 and d2)and the HBW value is read off a table,from the average of d1 and d2.

When the test results are reported,Brinell hardness is indicated with theletters HBW and a suffix indicating balldiameter, the mass with which the load

Vickers (HV)

In Vickers hardness testing a pyramid-shaped diamond with a square baseand a peak angle of 136° is pressedunder a load F against the materialwhose hardness is to be determined.After unloading, the diagonals d1 and d2

of the impression are measured and thehardness number (HV) is read off atable.

Principle of Brinell hardness testing

When the test re-sults are reported,Vickers hardness isindicated with theletters HV and asuffix indicating themass that exerted theload and (when re-quired) the loadingperiod, as illustrated bythe following example:HV 30/20 = Vickershardness determinedwith a load of 30 kgfexerted for 20 seconds.

F

136°

d2d1

was exerted and (when required) theloading period, as illustrated by thefollowing example: HBW 5/750/15 =Brinell hardness determined with 5 mmTungsten (W) ball and under load of750 kgf exerted for 15 seconds.

(HRC) which is read directly from a scaleon the tester dial or read-out.

Principle of Vickers hardness testing

HEAT TREATMENT

11

TENSILE STRENGTH

Tensile strength is determined on a testpiece which is gripped in a tensile test-ing machine and subjected to a succes-sively increasing tensile load until frac-ture occurs. The properties that arenormally recorded are yield strengthRp0,2 and ultimate tensile strength Rm,while elongation A5 and reduction ofarea Z are measured on the test piece.In general, it can be said that hardnessis dependent upon yield strength andultimate tensile strength, while elonga-tion and reduction of area are an indica-tion of toughness. High values for yieldand ultimate tensile strength generallymean low values for elongation andreduction of area.

Tensile tests are used mostly onstructural steels, seldom on tool steels.It is difficult to perform tensile tests athardnesses above 55 HRC. Tensile testsmay be of interest for tougher types oftool steel, especially when they are usedas high strength structural materials.These include e.g. Impax Supreme andOrvar 2 Microdized.

IMPACT TESTING

A certain quantity of energy is requiredto produce a fracture in a material. Thisquantity of energy can be used as ameasure of the toughness of the mate-rial, a higher absorption of energy indi-cating better toughness. The most com-mon and simplest method of determin-ing toughness is impact testing. A rigidpendulum is allowed to fall from aknown height and to strike a test speci-men at the lowest point of its swing.The angle through which the pendulumtravels after breaking the specimen ismeasured, and the amount of energythat was absorbed in breaking thespecimen can be calculated.

Several variants of impact testingare in use. The various methods differ inthe shape of the specimens. These areusually provided with a V- or U-shapednotch, the test methods being thenknown as Charpy V and Charpy U re-spectively.

HEAT TREATMENT

Choose suitable hardnesses for the ap-plication concerned. Be particularly care-ful to avoid temperature ranges that canreduce toughness after tempering.

Keep the risk of distortion in mindand follow recommendations concerningmachining allowances.

It is a good idea to specify stressrelieving on the drawings.

Some wordsof advice to tooldesignersCHOICE OF STEEL

Choose air-hardening steels for complextools.

DESIGN

Avoid:• sharp corners• notch effects• large differences in section

thicknesses.

These are often causes of quenchcracks, especially if the material iscooled down too far or allowed to standuntempered.

Unsuitabledesign

Preferredalternative

✗✗

Fillet

For the most part, tool steel has arather low toughness by reason of itshigh strength. Materials of low tough-ness are notch sensitive, for whichreason smooth, un-notched specimensare often used in the impact testing oftool steels. The results of the tests arecommonly stated in joules, or alterna-tively in kgm (strictly speaking kgfm),although J/cm2 or kgm/cm2 is some-times used instead, specially in CharpyU testing.

There are several other variants ofimpact testing which are used outsideSweden, e.g. DVM, Mesanger and—especially in English speaking coun-tries—Izod.

HEAT TREATMENT

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EuropeAustriaRepresentative officeUDDEHOLMAlbstraße 10DE-73765 NeuhausenTelephone: +49 7158 9865-0www.uddeholm.de

BelgiumUDDEHOLMEuropark Oost 7B-9100 Sint-NiklaasTelephone: +32 3 780 56 20www.uddeholm.be

CroatiaBÖHLER UDDEHOLM Zagrebd.o.o za trgovinuZitnjak b.b10000 ZagrebTelephone: +385 1 2459 301Telefax: +385 1 2406 790www.bohler-uddeholm.hr

Czech RepublicBÖHLER UDDEHOLM CZ s.r.o.Division UddeholmU Silnice 949161 00 Praha 6, RuzyneTelephone: +420 233 029 850,8www.uddeholm.cz

DenmarkUDDEHOLM A/SKokmose 8, BramdrupdamDK-6000 KoldingTelephone: +45 75 51 70 66www.uddeholm.dk

EstoniaUDDEHOLM TOOLING ABSilikatsiidi 7EE-11216 TallinnTelephone: +372 655 9180www.uddeholm.ee

FinlandOY UDDEHOLM ABRitakuja 1, PL 57FI-01741 VANTAATelephone: +358 9 290 490www.uddeholm.fi

FranceHead officeUDDEHOLMZ.I. de Mitry-Compans, 12 rue Mercier,FR-77297 Mitry Mory CedexTelephone: +33 (0)1 60 93 80 10www.uddeholm.fr

Branch officesUDDEHOLM S.A.77bis, rue de VesoulLa Nef aux MétiersFR-25000 BesançonTelephone: +33 (0)381 53 12 19

LE POINT ACIERSUDDEHOLM - Aciers à outilsZ.I. du Recou, Avenue de ChamplevertFR-69520 GRIGNYTelephone: +33 (0)4 72 49 95 61

LE POINT ACIERSUDDEHOLM - Aciers à outilsZ.I. Nord 27, rue François RochaixFR-01100 OYONNAXTelephone: +33 (0)4 74 73 48 66

GermanyHead officeUDDEHOLMHansaallee 321DE-40549 DüsseldorfTelephone: +49 211 5351-0www.uddeholm.de

Branch officesUDDEHOLMFalkenstraße 21DE-65812 Bad Soden/TSTelephone: +49 6196 6596-0

UDDEHOLMAlbstraße 10DE-73765 NeuhausenTelephone: +49 7158 9865-0

UDDEHOLMFriederikenstraße 14bDE-06493 HarzgerodeTelephone: +49 39484 727 267

Great BritainUDDEHOLM DIVISIONBOHLER-UDDEHOLM (UK) LIMITEDEuropean Business ParkTaylors Lane, OldburyGB-West Midlands B69 2BNTelephone: +44 121 552 5511Telefax: +44 121 544 2911www.uddeholm.co.uk

GreeceSTASSINOPOULOS-UDDEHOLMSTEEL TRADING S.A.20, Athinon StreetGR-Piraeus 18540Telephone: +30 210 4172 109www.uddeholm.gr

SKLERO S.A.Heat Treatment and Trading of SteelUddeholm Tool SteelsIndustrial Area of ThessalonikiP.O. Box 1123GR-57022 Sindos, ThessalonikiTelephone: +30 2310 79 76 46www.sklero.gr

HungaryUDDEHOLM TOOLING/BOKDunaharaszti, Jedlik Ányos út 25HU-2331 Dunaharaszti 1. Pf. 110Telephone/fax:+36 24 492 690www.uddeholm.hu

IrelandHead office:UDDEHOLM DIVISIONBOHLER-UDDEHOLM (UK) LIMITEDEuropean Business ParkTaylors Lane, OldburyUK-West Midlands B69 2BNTelephone: +44 121 552 5511Telefax: +44 121 544 2911www.uddeholm.co.ukDublin:Telephone: +353 1845 1401

ItalyUDDEHOLMDivisione della Bohler UddeholmItalia S.p.A.Via Palizzi, 90IT-20157 MilanoTelephone: +39 02 39 49 211www.uddeholm.it

LatviaUDDEHOLM TOOLING LATVIA SIAPiedrujas Street 7LV-1035 RigaTelephone: +371 7 702133latvia@assab.com

Branch officeUDDEHOLMBarrio San Martín de Arteaga,132Pol.Ind. TorrelarragoitiES-48170 Zamudio (Bizkaia)Telephone: +34 94 452 13 03

SwedenHead officeUDDEHOLM TOOLING SVENSKA ABAminogatan 25SE-431 53 MölndalTelephone: +46 31 67 98 50www.uddeholm.se

Branch officesUDDEHOLM TOOLING SVENSKA ABBox 45SE-334 21 AnderstorpTelephone: +46 371 160 15

UDDEHOLM TOOLING SVENSKA ABBox 148SE-631 03 EskilstunaTelephone: +46 16 15 79 00

UDDEHOLM TOOLING SVENSKA ABAminogatan 25SE-431 53 MölndalTelephone: +46 31 67 98 70

UDDEHOLM TOOLING SVENSKA ABNya Tanneforsvägen 96SE-582 42 LinköpingTelephone: +46 13 15 19 90

UDDEHOLM TOOLING SVENSKA ABDerbyvägen 22SE-212 35 MalmöTelephone: +46 40 22 32 05

UDDEHOLM TOOLING SVENSKA ABHonnörsgatan 24SE-352 36 VäxjöTelephone: +46 470 457 90

SwitzerlandHERTSCH & CIE AGGeneral Wille Strasse 19CH-8027 ZürichTelephone: +41 44 208 16 66www.hertsch.ch

TurkeyHead officeASSAB Korkmaz Celik A.S.Organize Sanayi Bölgesi2. Cadde No: 26 Y. Dudullu34776 UmraniyeTR-IstanbulTelephone: +90 216 420 1926www.assabkorkmaz.com

LithuaniaUDDEHOLM TOOLING ABBE PLIENAS IR METALAIT. Masiulio 18BLT-52459 KaunasTelephone: +370 37 370613, -669www.besteel.lt

The NetherlandsUDDEHOLMIsolatorweg 30NL-1014 AS AmsterdamTelephone: +31 20 581 71 11www.uddeholm.nl

NorwayUDDEHOLM A/SJernkroken 18Postboks 85, KalbakkenNO-0902 OsloTelephone: +47 22 91 80 00www.uddeholm.no

PolandBOHLER UDDEHOLM POLSKASp. z.o.o./Co. Ltd.ul. Kolejowa 291, Dziekanów Polski,PL-05-092 LomiankiTelephone: +48 22 429 2260, -203, -204www.uddeholm.pl

PortugalF RAMADA Aços e Industrias S.A.P.O. Box 10PT-3881 Ovar CodexTelephone: +351 256 580580www.ramada.pt

RomaniaBÖHLER-UDDEHOLM Romania SRLAtomistilor Str. No 96-102077125 - com. Magurele, Jud. Ilfov.Telephone: +40 214 575007Telefax: +40 214 574212

RussiaUDDEHOLM TOOLING CIS9A, Lipovaya Alleya, Office 509RU-197183 Saint PetersburgTelephone: +7 812 6006194www.uddeholm.ru

SlovakiaBohler-Uddeholm Slovakia s.r.o.divizia UDDEHOLMCsl.Armády 5622/5SK-036 01 MartinTelephone: +421 (0)434 212 030www.uddeholm.sk

SloveniaRepresentative officeUDDEHOLMDivisione della Bohler UddeholmItalia S.p.A.Via Palizzi, 90IT-20157 MilanoTelephone: +39 02 39 49 211www.uddeholm.it

SpainHead officeUDDEHOLMGuifré 690-692ES-08918 Badalona, BarcelonaTelephone: +34 93 460 1227www.acerosuddeholm.com

ˇ

HEAT TREATMENT

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AmericaArgentinaACEROS BOEHLER UDDEHOLM S.AMozart 401619-Centro Industrial GarinGarin-Prov.AR-Buenos AiresTelephone: +54 332 7444 440www.uddeholm.com.ar

BrazilAÇOS BOHLER-UDDEHOLM DOBRASIL LTDA– DIV. UDDEHOLMEstrada Yae Massumoto, 353CEP 09842-160BR-Sao Bernardo do Campo - SP BrazilTelephone: +55 11 4393 4560, 4554www.uddeholm.com.br

CanadaHead Office & WarehouseBOHLER-UDDEHOLM LIMITED2595 Meadowvale Blvd.Mississauga, ON L5N 7Y3Telephone: +1 905 812 9440www.bucanada.com

Branch WarehousesBOHLER-UDDEHOLM LIMITED3521 Rue AshbySt. Laurent, QC H4R 2K3Telephone: +1 514 333 8000

BOHLER-UDDEHOLM LIMITED730 Eaton Way - Unit #10New Westminister, BC V3M 6J9Telephone: +1 604 525 3354

Heat TreatingBOHLER-UDDEHOLMTHERMO-TECH2645 Meadowvale Blvd.Mississauga, ON L5N 7Y4Telephone: +1 905 812 9440

ColombiaAXXECOL S.A.Carrera 35 No 13-20Apartado Aereo 80718CO-Bogota 6Telephone: +57 1 2010700www.axxecol.com

ASTECO S.A.Carrera 54 No 35-12Apartado Aereo 663CO-MedellinTelephone: +57 4 2320122www.asteco.com

Dominican RepublicRAMCA, C. POR A.P-2289P.O. Box 025650Miami, Fl. 33102Telephone: +1 809 682 4011domrep@assab.com

EcuadorIVAN BOHMAN C.A.Apartado 1317Km 6 1/2 Via a DauleGuayaquilTelephone: +593 42 254111www.ivanbohman.com.ec

IVAN BOHMAN C.A.Casilla Postal 17-01370QuitoTelephone: +593 2 2248001www.ivanbohman.com.ec

El SalvadorACAVISA DE C.V.25 Ave. Sur, no 763Zona 1SV-San SalvadorTelephone: +503 22 71 1700www.acavisa.com

GuatemalaIMPORTADORA ESCANDINAVAApartado postal 11CGT-Guatemala CityTelephone: +502 23 659270guatemala@assab.com

HondurasACAVISA DE C.V.25 Ave. Sur, no 763Zona 1SV-San SalvadorTelephone: +503 22 71 1700www.acavisa.com

MexicoHead officeACEROS BOHLER UDDEHOLM S.A.de C.V.Calle Ocho No 2, Letra ”C”Fraccionamiento Industrial Alce BlancoC.P. 52787 Naucalpan de JuarezMX-Estado de MexicoTelephone: +52 55 9172 0242www.bu-mexico.com

Branch officeBOHLER-UDDEHOLM MONTERREY,NUEVO LEONLerdo de Tejada No.542Colonia Las VillasMX-66420 San Nicolas de Los Garza,N.L.Telephone: +52 81 83 525239

PeruC.I.P.E.S.AAv. Oscar R. Benavides(ante Colonial) No. 2066PE-Lima 1Telephone: +51 1 336 8673peru@assab.com

U.S.A.Head office and WarehouseBOHLER-UDDEHOLMCORPORATION2505 Millennium DriveElgin IL 60124Telephone: 1-630-883-3000 or1-800-652-2520Sales phone: 1-800-638-2520www.bucorp.com

Region East WarehouseBOHLER-UDDEHOLMCORPORATION220 Cherry StreetShrewsbury MA 01545

Region Central WarehouseBOHLER-UDDEHOLMCORPORATION548 Clayton Ct.Wood Dale IL 60191

Region West WarehouseBOHLER-UDDEHOLMCORPORATION9331 Santa Fe Springs RoadSanta Fe Springs, CA 90670

VenezuelaPRODUCTOS HUMAR C.A.Av. Bolivar, Zona IndustrialLa TrinidadEdificio. Distribuidora Agrofor, C.A.Piso 3, VE-Caracas 1080Telephone: +58 212 942 1994 or+58 212 915 7073humar@assab.com

Other Countries in AmericaASSAB INTERNATIONAL ABBox 42SE-171 11 Solna, SwedenTelephone: +46 8 564 616 70www.assab.se

Asia & PacificAustraliaBOHLER UDDEHOLM Australia129-135 McCredie RoadGuildford NSW 2161Private Bag 14AU-SydneyTelephone: +61 2 9681 3100www.buau.com.au

BangladeshASSAB INTERNATIONAL ABP.O. Box 17595Jebel AliAE-DubaiTelephone: +971 488 12165www.assab.se

North ChinaHead officeASSAB Tooling (Beijing) Co LtdNo.10A Rong Jing Dong JieBeijing Economic Development AreaBeijing 100176, ChinaTelephone: +86 10 6786 5588www.assabsteels.com

Branch officesASSAB Tooling (Beijing) LtdDalian Branch8 Huanghai Street, Haerbin RoadEconomic & Technical Develop. DistrictDalian 116600, ChinaTelephone: +86 411 8761 8080

ASSAB Qingdao OfficeRoom 2521, Kexin MansionNo. 228 Liaoning Road, Shibei DistrictQingdao 266012, ChinaTelephone: +86 532 8382 0930

ASSAB Tianjin OfficeNo.12 Puwangli Wanda XinchengXinyibai Road, Beichen DistrictTianjin 300402, ChinaTelephone: +86 22 2672 0006

Central ChinaHead officeASSAB Tooling Technology(Shanghai) Co LtdNo. 4088 Humin RoadXinzhuang Industrial ZoneShanghai 201108, ChinaTelephone: +86 21 5442 2345www.assabsteels.com

Branch officesASSAB Tooling Technology(Ningbo) Co LtdNo. 218 Longjiaoshan RoadVehicle Part Industrial ParkNingbo Economic & Technical Dev.ZoneNingbo 315806, ChinaTelephone: +86 574 8680 7188

ASSAB Tooling Technology(Chongqing) Co LtdPlant C, Automotive Industrial lParkChongqing Economic & TechnologicalDevelopment ZoneChongqing 401120, ChinaTelephone: +86 23 6745 5698

South ChinaHead officeASSAB Steels (HK) LtdRoom 1701–1706Tower 2 Grand Central Plaza138 Shatin Rural Committee RoadShatin NT - Hong KongTelephone: +852 2487 1991www.assabsteels.com

Branch officesASSAB Tooling (Dongguan) Co LtdNorthern DistrictSong Shan Lake Science & TechnologyIndustrial ParkDongguan 523808, ChinaTelephone: +86 769 2289 7888www.assabsteels.com

ASSAB Tooling (Xiamen) Co LtdFirst Floor Universal WorkshopNo. 30 Huli ZoneXiamen 361006, ChinaTelephone: +86 592 562 4678

Hong KongASSAB Steels (HK) LtdRoom 1701-1706Grand Central Plaza, Tower 2138 Shatin Rural Committee RoadShatin NT, Hong KongTelephone: +852 2487 1991www.assabsteels.com

IndiaASSAB Sripad Steels LTDT 303 D.A.V. ComplexMayur Vihar Ph I ExtensionIN-Delhi-110 091Telephone: +91 11 2271 2736www.assabsripad.com

ASSAB Sripad Steels LTD709, Swastik ChambersSion-Trombay RoadChemburIN-Mumbai-400 071Telephone: +91 22 2522-7110, -8133www.assabsripad.com

ASSAB Sripad Steels LTDPadmalaya TowersJanaki AvenueM.R.C. NagarIN-Chennai-600 028Telephone: +91 44 2495 2371www.assabsripad.com

ASSAB Sripad Steels LTD19X, D. P. P. RoadNaktola Post OfficeIN-Kolkata-700 047Telephone: +91 (33) 400 1645www.assabsripad.com

ASSAB Sripad Steels LTDGround floor, Plot No 11-6-8Opp IDPL Factory Out GateBalanagarIN-Hyderabad-500 037Telephone: +91 (40) 2377 8148www.assabsripad.com

IndonesiaHead officePT ASSAB Steels IndonesiaJl. Rawagelam III No. 5Kawasan Industri PulogadungJakarta 13930, IndonesiaTelephone: +62 21 461 1314www.assabsteels.com

HEAT TREATMENT

14

Branch officesSURABAYA BRANCHJl. Berbek Industri 1/23Surabaya Industrial Estate, RungkutSurabaya 60293, East Java, IndonesiaTelephone: +62 31 843 2277

MEDAN BRANCHKomplek Griya Riatur IndahBlok A No.138Jl. T. Amir HamzahHalvetia Timur, Medan 20124Telephone: +62 61 847 7935/6

BANDUNG BRANCHKomp. Ruko Bumi KencanaJl. Titian Kencana Blok ENo.5 Bandung 40233Telephone: +62 22 604 1364

TANGERANG BRANCHPusat Niaga CibodasBlok C No. 7 TangerangTelephone: +62 21 921 9596, 551 2732

SEMARANG BRANCHJl. Imam Bonjol No.155R.208 Semarang 50124Telephone: +62 358 8167

IranASSAB INTERNATIONAL ABP.O. Box 19395IR-1517 TEHRANTelephone: +98 21 888 35392www.assabiran.com

IsraelPACKER YADPAZ QUALITYSTEELS LtdP.O. Box 686Ha-Yarkon St. 7, Industrial ZoneIL-81106 YAVNETelephone: +972 8 932 8182www.packer.co.il

JapanUDDEHOLM KKAtago East Building3-16-11 Nishi ShinbashiMinato-ku, Tokyo 105-0003, JapanTelephone: + 81 3 5473 4641www.assabsteels.com

JordanENGINEERING WAY Est.P.O. Box 874Abu AlandaJO-AMMAN 11592Telephone: +962 6 4161962engineeringway@assab.com

MalaysiaHead officeASSAB Steels (Malaysia) Sdn BhdLot 19, Jalan Perusahaan 2Batu Caves Industrial Estate68100 Batu CavesSelangor MalaysiaTelephone: +60 3 6189 0022www.assabsteels.com

Branch officesBUTTERWORTH BRANCHPlot 146aJalan Perindustrial Bukit Minyak 7Kawasan Perindustrial Bukit Minyak14000 Bukit Mertajam, SPT PenangTelephone: +60 4 507 2020

JOHOR BRANCHNo. 8, Jalan Persiaran TeknologiTaman Teknologi81400 SenaiJohor DT, MalaysiaTelephone: +60 7 598 0011

New ZealandVIKING STEELS25 Beach Road, OtahuhuP.O. Box 13-359, OnehungaNZ-AucklandTelephone: +64 9 270 1199www.ssm.co.nz

PakistanASSAB International ABP.O. Box 17595Jebel AliAE-DubaiTelephone: +971 488 12165www.assab.se

PhilippinesASSOCIATED SWEDISH STEELSPHILS Inc.No. 3 E. Rodriguez Jr., AvenueBagong Ilog, Pasig CityPhilippinesTelephone: +632 671 1953/2048www.assabsteels.com

Republic of KoreaHead officeASSAB Steels (Korea) Co Ltd116B-8L, 687-8, Kojan-dongNamdong-kuIncheon 405-310, KoreaTelephone: +82 32 821 4300www.assabsteels.com

Branch officesBUSAN BRANCH14B-5L, 1483-9, Songjeong-dongKangseo-ku, Busan 618-270, KoreaTelephone: +82 51 831 3315

DAEGU BRANCHRoom 27, 7-Dong2 FIndustry Materials Bldg.1629Sangyeog-Dong, Buk-KuKorea-Daegu 702-710Telephone: +82 53 604 5133

LebanonWARDE STEEL & METALS SARL METCharles Helou Av, Warde BldgP.O. Box 165886LB-BeirutTelephone: +961 1 447228lebanon@assab.com

Saudi ArabiaASSAB INTERNATIONAL ABP.O. Box 255092SA-Riyadh 11353Telephone: +966 1 4466542assab@emirates.net.ae

SingaporeHead office PacificASSAB Pacific Pte Ltd171, Chin Swee RoadNo. 07-02, SAN CentreSG-Singapore 169877Telephone: +65 6534 5600www.assabsteels.com

JurongASSAB Steels Singapore (Pte) Ltd18, Penjuru CloseSG-608616 SingaporeTelephone: +65 6862 2200

Sri LankaGERMANIA COLOMBO PRIVATE Ltd.451/A Kandy RoadLK-KelaniyaTelephone: +94 11 2913556www.iwsholdings.com

SyriaWARDE STEEL & METALS SARL METCharles Helou Av, Warde BldgP.O. Box 165886LB-BeirutTelephone: +961 1 447228lebanon@assab.com

TaiwanHead officeASSAB Steels (Taiwan) Co LtdNo. 112 Wu Kung 1st Rd.Wu Ku Industry ZoneTW-Taipei 248-87, Taiwan (R.O.C.)Telephone: +886 2 2299 2849www.assabsteels.com

Branch officesNANTOU BRANCHNo. 10, Industry South 5th RoadNan Kang Industry ZoneNantou 540-66, Taiwan (R.O.C.)Telephone: +886 49 225 1702TAINAN BRANCHNo. 180, Yen He Street,Yong Kang CityTainan 710-82, Taiwan (R.O.C.)Telephone: +886 6 242 6838

ThailandASSAB Steels (Thailand) Ltd9/8 Soi Theedinthai,Taeparak Road, Bangplee,Samutprakarn 10540, ThailandTelephone: +66 2 385 5937,+66 2 757 5017www.assabsteels.com

United Arab EmiratesASSAB INTERNATIONAL ABP.O. Box 17595Jebel AliAE-DubaiTelephone: +971 488 12165www.assab.se

VietnamCAM Trading Steel Co Ltd90/8 Block 5, Tan Thoi Nhat WardDistrict 12, Ho Chi Minh CityVietnamTelephone: +84 8 5920 920www.assabsteels.com

Other AsiaASSAB INTERNATIONAL ABBox 42E-171 11 Solna, SwedenTelephone: +46 8 564 616 70www.assab.se

AfricaEgyptMISR SWEDEN FORENGINEERING IND.Montaser Project No 20Flat No 14Al Ahram Street-El TabiaEG-Giza CairoTelephone: +20 2 7797751www.assab.se

KenyaSANDVIK Kenya LtdP.O. Box 18264Post code 00500KE-NairobiTelephone: +254 20 532 866info@sandvik.co.ke

MoroccoMCM Distribution4 Bis, Rue 8610 - Z.I.2035 Charguia 1TN-TunisTelephone: + 216 71 802 479

South AfricaUDDEHOLM Africa (Pty.) Ltd.P.O. Box 539ZA-1600 Isando/JohannesburgTelephone: +27 11 974 2791www.bohler-uddeholm.co.za

TunisiaMCM Distribution4 Bis, Rue 8610 - Z.I.2035 Charguia 1TN-TunisTelephone: + 216 71 802 479www.mcm.com.tn

ZimbabweRepresentative office:UDDEHOLM Africa (Pty.) Ltd.P.O. Box 539ZA-1600 Isando/JohannesburgTelephone: +27 11 974 2781www.bohler-uddeholm.co.za

Other African CountriesASSAB INTERNATIONAL ABBox 42SE-171 11 Solna, SwedenTelephone: +46 8 564 616 70www.assab.se

www.assab.com www.uddeholm.com www.uddeholm.com

Network of excellenceUddeholm is present on every continent. This ensures you

high-quality Swedish tool steel and local support wherever you

are. Assab is our wholly-owned subsidiary and exclusive sales

channel, representing Uddeholm in various parts of the world.

Together we secure our position as the world’s leading supplier

of tooling materials.

HA

GFO

RS KLARTEX

T U0712X

X

Uddeholm is the world’s leading supplier of tooling materials. This

is a position we have reached by improving our customers’ everyday

business. Long tradition combined with research and product develop-

ment equips Uddeholm to solve any tooling problem that may arise.

It is a challenging process, but the goal is clear – to be your number one

partner and tool steel provider.

Our presence on every continent guarantees you the same high quality

wherever you are. Assab is our wholly-owned subsidiary and exclusive

sales channel, representing Uddeholm in various parts of the world.

Together we secure our position as the world’s leading supplier of

tooling materials. We act worldwide, so there is always an Uddeholm

or Assab representative close at hand to give local advice and support.

For us it is all a matter of trust – in long-term partnerships as well as in

developing new products. Trust is something you earn, every day.

For more information, please visit www.uddeholm.com or www.assab.com