SteelSheet

2-6-1 Marunouchi, Chiyoda-ku,Tokyo 100-8071 JapanTel: +81-3-6867-4111

VIBLESSTM

U044en_01_201904f© 2019 NIPPON STEEL CORPORATION

VIBLESSTMwww.nipponsteel.com Steel

Sheet

2-6-1 Marunouchi, Chiyoda-ku,Tokyo 100-8071 JapanTel: +81-3-6867-4111

VIBLESSTM

U044en_01_201904f© 2019 NIPPON STEEL CORPORATION

VIBLESSTMwww.nipponsteel.com

Noise-prevention Methods

Glass Wool, Wood, Wool,Cement Excelsior Board, Concrete,Thick-Gauge Steel Sheet

Ⓐ Sound Insulation and Absorption

VIBLESS, Damping Sheet, Damping Alloy, Rubber, Wood, Plastics, etc.

Ⓑ Vibration Damping and Absorption

VIBLESS is effective in the case of Ⓑ above. It demonstrates particularly high performance when used in direct contact with a source of vibration or when incorporated in such a source.

1

Noise is occurring more frequently in daily life. Accordingly, it seems that because of this,

even our hearts produce heartless sounds. Putting much value on peaceful moments and

quiet places — such feelings are becoming more apparent not only in industry but in our

homes as well.

One powerful way to create quietude is to use VIBLESS, a vibration-damping

steel sheet supplied by NIPPON STEEL. This product not only maintains advantages such

as the high strength and excellent workability that are peculiar to steel sheets but also

offers high vibration-damping capacity. VIBLESS is used widely as a material in

automobile parts, electrical home appliances, and building construction where it helps to

create quietness.

Preserving the Quiet VIBLESS™

Major Features of VIBLESS ❶ Outstanding Vibration-damping Capacity

❷ Excellent Press-formability

❸ Available Spot Welding for Certain Types

❹ High-temperature Baked Finish Available with Thermosetting Type

❺ High Reliability Demonstrated by Proven Durability and Abundant Records of Usage in Such Fields as Automobile Oil Pans and Electrical Home Appliances

❻ Nearly Identical Treatment for Both VIBLESS Scrap and General Steel Scrap

1. Noise and Noise Prevention, and Vibration-damping Capacity of VIBLESS

Contents

1. Noise and Noise Prevention, and Vibration-damping Capacity of VIBLESS……1

2. Structure and Vibration-damping Effect of VIBLESS……2 3. Classification Symbols and Typical Types of VIBLESS……4 4. Size Availability of VIBLESS……5 5. Properties of VIBLESS……6 6. Heat Resistance……8 7. Durability……9 8. Typical Applications……10 9. Packaging and Markings……1210. Reference Information on Usage……13References VIBLESS Production Line……14 Methods for Measuring Vibration-damping Capacity……15 Methods for Measuring Adhesive Strength……15

Based on the provisions specified in Article 68-26, Item 1 of the Building Standard Law of Japan (including cases covered by Article 88, Item 1 of the Law), VIBLESS has been approved by the Minister of Land, Infrastructure and Transport as a material conforming to the provisions on incombustible materials specified in Article 2, No. 9 of the Law and in Article 108-2 of the Enforcement Order of the Law.

Notice: While every effort has been made to ensure the accuracy of the information contained within this publication, the use of the information is at the reader’s risk and no warranty is implied or expressed by NIPPON STEEL CORPORATION with respect to the use of the information contained herein. The information in this publication is subject to change or modification without notice. Please contact the NIPPON STEEL CORPORATION office for the latest information. Please refrain from unauthorized reproduction or copying of the contents of this publication.The names of our products and services shown in this publication are trademarks or registered trademarks of NIPPON STEEL CORPORATION, affiliated companies, or third parties granting rights to NIPPON STEEL CORPORATION or affiliated companies. Other product or service names shown may be trademarks or registered trademarks of their respective owners.

Noise-prevention methods are broadly divisible into two categories:Ⓐ The absorption or insulation of noiseⒷ The damping of vibrations that generate noise, thus minimizing noise

2 3

2. Structure and Vibration-damping Effect of VIBLESS

StructureStructurally, VIBLESS consists of two steel sheets sandwiching an approximately 40μm-thick layer of visco-elastic resin. The vibration-damping mechanism of this sheet is based on the shear deformation of the visco-elastic resin which transforms vibration energy into thermal energy.

Vibration-damping Effect and Characteristics(1) The vibration-damping capacity is usually given by the loss factor “ η ”. The higher this value, the

greater the vibration-damping effect. VIBLESS is available for room-, intermediate- and high-temperature uses, so that its vibration-damping potential may be fully utilized according to service temperature. (Fig. 1)

(2) Also available is VIBLESS for new intermediate-temperature use with an effective temperature range from room to high temperature, though it is slightly inferior in vibration-damping performance.

Shear deformation of the visco-elastic resin layer caused by vibration has the effect of damping vibration.

Shear

40μm

Visco-elastic Resin Layer

Steel Sheets

Steel Sheet

Steel Sheet

Resin Layer About 40μm Thick

-20 0

7

23

57

10-1

23

57

100

10-2

20 40 60 80 100 120

For Room-temperature Use

For Intermediate-temperature Use

For High-temperature Use

Temperature (°C)

Loss

Fac

tor

( η)

Relation Between the Loss Factor of VIBLESS and TemperatureFig. 1

at 500 Hz

(3) A comparison of the loss factor “ η ” of VIBLESS with that of other materials is shown in Fig. 2; their respective vibration-damping wave patterns are given in Fig. 3.

VIBLESS is superior in vibration-damping and has the high strength inherent in steel sheet.

(4) Fig. 4 gives loss factors measured at respective temperatures when oil has been poured into an actual oil pan. It shows the excellent vibration-damping capacity of VIBLESS.

(5) Sound-insulation Effect of VIBLESS The sound transmission loss of VIBLESS follows the law of mass. When compared with that

of ordinary steel sheet, it has the following characteristics. ① No lowering of the sound transmission loss at resonance coincidence② Sometimes sound-insulating materials will themselves vibrate and generate sound due to

the transmission of vibrations caused by large sound pressure or vibrations generated at the sound source. VIBLESS suppresses these vibrations, preventing the generation of sound.

Relation Between the Vibration-damping Capacity and Strength of Individual Materials at Room Temperature

0.0001 0.001 0.01 0.1

1

10

100

1000

Greater Vibration-damping Capacity →Loss Factor (η)

Tens

ile S

tren

gth

(N/m

m2)

Steel Sheet

Vibration-damping Alloy

Vibration-damping Material-laminated Steel Sheet

Plastics Rubber

Wood

VIBLESS

Fig. 2

20 40 60 80 100 1203

57

10-223

57

10-1

Oil Temperature (°C)

Loss

Fac

tor

( η)

Point of Measurement

Cold-rolled Steel Sheet

Relation Between Loss Factor and Oil Temperature When VIBLESS is Used in Oil Pans

Fig. 4

VIBLESS

126 200 315 500 800 1.25K 2K 3.15K 5K 8K

10

20

30

40

50

Ordinary Sound (90 dB) Intense Sound (110 dB)Vibration-damping Sheet Steel Sheet Mass Line

Frequency (Hz)

Sou

nd T

rans

mis

sion

Los

s (d

B)

VIBLESS

Ordinary Steel Sheet

Law of Mass

(5)-①

(5)-②

50 msec

50 msec

50 msec

50 msec

( )

( )

( )

( )

Material (Thickness) Loss Factor (η) Vibration-damping Wave Pattern

VIBLESS(0.8 + 0.8 mm)

Vibration-damping Mate-rial (2.0 mm)-laminated Steel Sheet (0.8 mm)

Vibration-damping Alloy (YUS 430D)(1.6 mm)

Cold-rolled Steel Sheet (1.6 mm)

Resonant Frequency 182 Hz

Resonant Frequency 121 Hz

Resonant Frequency 209.3 Hz

Resonant Frequency 219.2 Hz

0.3

0.1

0.02

0.0005

Loss Factor and Corresponding Vibration-damping Wave Pattern

Fig. 3

4 5

3. Classification Symbols and Typical Types of VIBLESS

4. Size Availability of VIBLESS

❶ Classification Symbols for VIBLESSSymbols in the specifications of VIBLESS mean :

❷ Typical Characteristics of VIBLESSThe available types of VIBLESS vary with service temperature.Please select the most suitable type.

❸ Coating Mass Symbol of VIBLESSPlease refer to the standards for such base steel sheets as electrogalvanized sheets and iron-zinc alloy-coated steel sheets.

❹ Surface Treatment of VIBLESSBecause the available surface treatments differ according to the type of coating, please consult us.

Examples of Classification Symbols

Notes •VIBLESS using steel sheets other than those listed are available. Please consult us.

Notes •The data shown are for a typical thermosetting resin and general type VIBLESS of commercial grade using cold-rolled steel sheets, 1.6 (0.8 + 0.8) mm thick.

① Measurement examples by means of the center-support stationary excitation method conforming to JIS G 0602 ② Shear adhesive strength : Measurement examples conforming to JIS K 6850 ③ T-peel strength : Measurement examples conforming to JIS K 6854•N/cm2 = 9.80665 × kgf/cm2, N/25 mm = 9.80665 × kgf/25 mm

Example

Grade (commercial)

Type of Lower Sheet(ZINKOTE, Electrogalvanized Sheet)

Type of Upper Sheet(ZINKOTE, Electrogalvanized Sheet)

V E E C

Vibless

Type of Sheet CommercialGrade

Drawing Grade

Deep-drawing Grade

Extradeep-drawing Grade Remarks

Cold-rolled Steel Sheet VCCC VCCD VCCE VCCX

Electrogalvanized Steel Sheet VEEC VEED VEEE VEEX ZINKOTE

Iron-Zinc Alloy-coated Steel Sheet VAAC VAAD VAAE — DURGRIP (Galvannealed)

ClassificationApplicable

Temperature Range (°C)

Weldability

Vibration-damping Property Adhesive Strength

η -max500 Hz

Shear Adhesion(N/cm2)

T-peel Strength(N/25 mm)

Room-temperature Use 20 〜 40 ○ 0.20 800 100

Intermediate-temperature Use 40 〜 80 ○ 0.15 1000 140

High-temperature Use 70 〜 100 ○ 0.15 1500 180

M No Treatment

QM High-functional Chromate-free Treatment

QB Chromate-free Phosphate Treatment

1250600

1.0 + 1.0

0.4 + 0.4

0.6 + 0.6

① Cold-rolled Steel Sheets

Extradeep- drawing Grade

Commercial ～Deep-drawing Grades

Sheet Width (mm)

Thic

knes

s (m

m)

（U

pp

er +

Low

er）

1250600

1.0 + 1.0

0.4 + 0.4

0.6 + 0.6

② Electrogalvanized Steel Sheets

Commercial ～ Deep-drawing Grades

Extradeep- drawing Grade

Sheet Width (mm)

Thic

knes

s (m

m)

（U

pp

er +

Low

er）

1250600

1.0 + 1.0

0.4 + 0.40.5 + 0.5

③ Iron-Zinc Alloy-coated Steel Sheets

CommercialGrade

Drawing Grade, Deep-drawing Grade

Sheet Width (mm)

Thic

knes

s (m

m)

（U

pp

er +

Low

er）

: Because the available size range changes slightly

depending on the kind of steel sheets and

viscoelastic resins adopted, please consult us

concerning the details of size availability.

6 7

5. Properties of VIBLESS

❶ Examples of Tensile Test Values (Test Piece: JIS No. 5) ❹ Resistance Weldability

❷ Formability of VIBLESS

❸ Fatigue Property

Type of Base Sheet Yield Point(N/mm2)

Tensile Strength(N/mm2)

Elongation(%) r̄̄ Value

Cold-rolled Steel Sheets (t = 0.8 mm) of Deep-drawing Grade 150 290 50 2.00

VIBLESS（t = 0.8 + 0.8）

For Room-temperature Use 146 283 50 2.01

For Intermediate-temperature Use 146 285 50 2.02

For High-temperature Use 145 285 51 2.02

⃝ The yield point and tensile strength of VIBLESS are slightly lower than those of the cold-rolled steel sheets used.

⃝ The r value of VIBLESS is slightly higher than that of cold-rolled steel sheets used.

50 100 150 200

Relation Between Various Kinds of Formability and Shear Adhesive Strength

Shear Adhesive Strength (kgf/cm2)

Poo

r ←

Form

abili

ty →

Goo

d

Body Wrinkling Resistance

End Hardenability (Flange up)Flange Wrinkling Resistance

Deep Drawability

Deep Drawability

Flange Wrinkle

Flange up

Body Wrinkle

Levels of Ordinary Steel Sheets of Half the Thickness

Levels of Ordinary Steel Sheet of the Same Thickness

→→

at 25°C

104 1052 3 5 7 1062 3 5 7 1072 3 5 7 2 310

20

30

Plane-bending Fatigue Test

Cold-rolled Steel Sheet (1.6 t)

VIBLESS (0.8/0.8 t)

VIBLESS (Weldable)(0.8/0.8 t)

Number of Cycles to Failure （cycle）

Str

ess

(kgf

/mm

2 )

170 180 190 200 210 2200

5

10

15

20

mm100

In general, formability improves with increased adhesive strength.In drawing VIBLESS, apply a higher blank holding force than when working with ordinary steel sheet.Since the properties of VIBLESS vary with the type of the intermediate visco-elastic resin layer, please consult us before using.

•

•

•

Relation Between Cylindrical Deep-drawing limit and Blank Holding Force

Blank Diameter (mmφ)

Bla

nk H

old

ing

Forc

e (to

n)

Cold-rolled Steel Sheet for Deep Drawing (1.2 mm Thick)

Lubricant :Rust-preventive Oil

Wrinkling Limit

Breaking Point

VIBLESS (0.6 + 0.6 mm)

The fatigue property of VIBLESS is virtually equal to that of cold-rolled steel sheet, as shown in the figure.

① VIBLESS (Commercial Grade)Welding of VIBLESS requires a supporting electrode system, because of the intermediate layer of nonconductive, elastic high polymer. The use of the supporting electrode system developed by NIPPON STEEL enables both spot and projection welding to be performed in a manner similar to that for cold-rolled steel sheet.

② Weldable VIBLESSConductive metal particles are added to the intermediate resin layer. This permits resistance welding without the need for the aforementioned by-pass circuit.

③ Proper Welding RegionProper Welding Conditions for Spot Welding are as Follows :

Example of Current Application By By-pass Circuit

Supporting Electrode

(NIPPON STEEL Patented)

Conductor

VIBLESS

(ℓ = 30 mm)Interval Invariable

(Seq

uent

ial

Op

erat

ion)

Mai

n E

lect

rod

e

Resin

Joining Material

Electrode

Hand Vice

Weld Spot

20 R

(Cu)

Supporting Electrode SystemWeld Spot SystemBy-pass Jig System

Metal Particles

Steel Sheet

Steel Sheet

Steel Sheet

Steel Sheet

Resin Layer

Resin Layer

Metal Particles

2 4 6 8 10 12 14 16 18 20 22

8

14

20

8

14

20

8

14

20

VIB

LES

Sto

VIB

LES

SV

IBLE

SS

to

Col

d-r

olle

d S

heet

Col

d-r

olle

d S

heet

to C

old

-rol

led

She

et

Test Pieces to be Welded

Welding Current (kA)

Wel

din

g Ti

me

( ∞)

8 9

❺ Arc Welding

5. Properties of VIBLESS

In arc-welding of VIBLESS to ordinary steel sheet, arrange the ordinary steel sheet in the lower position. (Photo①)When arc-welding VIBLESS to VIBLESS, heat penetration into the resin layer of the lower VIBLESS would cause the resin to gasify and erupt out of the joint, resulting in arc instability. It is recommended, therefore, that arc-welding be performed under low heat-input conditions to avoid such heat penetration. (Photo②)

① ②

❻ Control of Aged Lowering of Screw Torque Loss Due to Addition of Metallic Fillers

1. Test Method • Size of test piece: 1.6 mm(0.8 + 0.8) × 30 × 300 mm• Drilling: Drilling in a diameter of 6.5 mm and at a pitch of 50 mm → A set of M6 bolt, VIBLESS, washer and nut• Initial fastening force: Set at 100 kgf・cm (9.8 N・m)• Measurement of initial torque in the case of incremental fastening at room temperature after retaining in the prescribed time at 80 °C

2. Results • Because of the addition of metallic fillers, maximum torque loss is about 20 % even at 80 °C. Further, torque loss occurs within several hours after the initial addition of filler but remains nearly constant afterwards.

0.1 100010

50

100110

10 100

VIBLESS with Addition of Metallic Fillers

VIBLESS without Addition of Metallic Fillers

Time (hr)

Bol

t Fa

sten

ing

Torq

ue

(kg

f ・cm

)

Aged Characteristics of Bolt Fastening Torque in VIBLESS (80°C� After Lapse of Time)

6. Heat Resistance

0.2

100 200

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

100 ˚C80 ˚C60 ˚C

• Measurement of adhesive strength at room temperature

Time (hr)

Ad

hesi

ve S

tren

gth

Rat

io

Bef

ore

and

Aft

er H

eatin

g

Change in Adhesive Strength Due to Heating(In the case of fixing the temperature level and then changing the lapse of time)

1.0

0160 180 200 220 240

Shear Adhesive Strength

T-peel Strength

Temperature ( ˚C) (30-minute Heating at Each Temperature Level)

Ad

hesi

ve S

tren

gth

Rat

io

Bef

ore

and

Aft

er H

eatin

g

Change in Adhesive Strength Due to High-temperature Heating(In the case of fixing the lapse of time and then changing the temperature level)

7. Durability

Shown below are the results of a study concerning VIBLESS quality changes in various conceivable service environments. They show that VIBLESS undergoes hardly any deterioration in performance, providing excellent quality assurance in application.(Resin : thermo-setting type for high-temperature application)

4

0 200 400 600 800 1000

2

8

6

4

10-1 at 140°C

Heat-resistant Durability Test

Heating Time (hr)

Loss

Fac

tor

( η m

ax)

300

mm

Electromagnet

535 g Steel Ball

Test Piece (0.8 ＋ 0.8) × 200 × 200

Rubber (MV - 45) 15 mm

Foam Polystyrene

Results: No Peel andCrack at -30 °C × 5 hrs.

Low-temperature Resistance Test

4

6

0 200 400 600 800 1000 1200

2

8

6

10-1 at 43°C (Water Sprinkling 12 min./hr)

Weathering Test

Exposure Time (hr)

Loss

Fac

tor

( η m

ax) Temperature : 150°C

Oil : Mineral Oil4

6

0 10 15 20 30 35 40 1000

2

8

6

10-1

Oil Resistance Test

Immersion Time (min)

Loss

Fac

tor

( η m

ax)

Immersion Into City Water (20 ～ 25°C)

4

6

0 20 40 60 80 100 120 135

8

2

6

4

10-1

Water Resistance Test

Immersion Days (day)

Loss

Fac

tor

( η m

ax)

4

6

0 10

8

2

6

10-1

1 Cycle ＝

-30°C × 7.5 hr＋

R.T. × 0.5 hr＋

90°C × 15.5 hr＋

R.T. × 0.5 hr

Thermal Shock Resistance Test

Number of Cycles

Loss

Fac

tor

( η m

ax)

4

6

0 20

8

2

6

4

10-1

240°C

High-temperature Durability Test

Heating Time (min)

Loss

Fac

tor

( η m

ax)

4

6

0 440

8

2

6

10-1 at 40°C × 50 pphm

Ozone Resistance Test

Exposure Time (hr)

Loss

Fac

tor

( η m

ax)

Chain housing

Dash panel

Engine belt cover

Oil pan (Gasoline) Oil pan (Diesel)

Seat-back center

Wheelhouse

Ship wall

Noise-prevention wall

Roofing, Floor, Staircase

Roofing

Curtain rail

HDD cover

Dryer drum

HopperMotor base of fan heater

Washing machine body

10 11

8. Typical Applications

Classification Application Examples

Automobiles

Engine oil pan (Diesel, Gasoline), Mission oil pan, Engine cover, Wheelhouse, Dash panel, Floor panel, Room partition, Seat-back center, Door panel, Roofing, Brake part, Horn parts, Belt cover, Cross members

Electrical Machines

Washing machine body, Dryer drum, Fan-heater housing, Speaker frame, Cover and other components of acoustic equipment (Video cassette recorder, Compact disc player, etc.), Printer components, Housing for hot-water supply pot, Air-conditioner components, Components of antenna for BS broadcasting, Copy machine components, Motor cover, Motor fan cover, Motor frame, Switchbox

Building Materials

and Others

Roofing, Floor, Staircase, Shutter, Curtain rail, Shoot, Hopper and cover for industrial machinery, Various types of noise-prevention walls, Steel furniture, Air conditioner duct, Dispensing chutes of vending machines, Ship wall

12 13

❶ Example of Packaging

❷ Example of Marking on Packaging Label

(The form of packaging differs according to the distance and method of transport.)

9. Packaging and Markings 10. Reference Information on Usage

No Steel Cover on Coil Inside and OutsideExample of V.C.I Paper or Film Packaging[Coil]

Label

Steel Cover

Inside Angle

V.C.I. Paper

Outer Ring

Hoop

A

BC

VEEX : J S M NDD

② Division of Resins

③ Symbol of Temper Grade

① Classified Symbols

Item No. Item Markings

VIBLESSCommodity Name

Specifications

Dimensions

⑥ Symbol of Oiling

④ Symbol of Surface Finish (Upper and Lower Steel Sheets)

Division General WeldableRoom-

temperature UseIntermediate-

temperature UseHigh-

temperature Use

J

Q

K

G

I

E

H : Heavy Oiling L : Light Oiling N : Normal Oiling X : Nonoiling

⑤ Symbol of Surface Treatment

M : Nontreatment QM : High-functional Chromate-free Treatment QB : Chromate-free Phosphate Treatment

Dimensions for Ordering Thickness (Upper Sheet Thickness + Lower Sheet Thickness) × Width × Length (C. in the Case of Coil) Note : The Thickness of the Intermediate Resin Layer is not Included in the Thickness for Ordering.

A

B

C

VIBLESS — a composite material composed of steel sheet and visco-elastic resin — offers characteristics different from those of ordinary steel sheets. Special care should be given to the following points:

❶ Shearing/Cutting (1) Shearing and blanking: Adjust the clearance to half that for ordinary steel sheet. Adoption of clearances similar to that of ordinary steel sheet is likely to cause large burring.(2) For fusion-cutting, select the methods characterized by a small beam diameter, such as laser beam cutting. In plasma cutting, slight unevenness occurs on the cut surface. Since gas cutting is likely to cause burning and evaporation of the visco-elastic resin, which would make normal cutting difficult, gas cutting should be avoided.

❷ Forming (1) Because VIBLESS is more likely to wrinkle during drawing than ordinary steel sheets, higher blanking force should be adopted (refer to 5-(2) Formability of VIBLESS). In particular, in drawing parts for which forming is difficult, the plastic flowing performance of the visco-elastic resin constitutes an important factor that makes preliminary testing essential.

(2) In bending of VIBLESS, flange bending may occur due to a difference in residual stress between the upper and lower steel sheets (refer to paragraph 5-(3) Bendability). Countermeasures against this include:

① Materials: To differentiate thickness between the upper and lower steel sheets (however, this lessens the vibration-damping effect).

② Design: To adopt a larger bending radius

③ Fabrication: To extend the die width (ten times or more the sheet thickness is desirable). V-cutting (refer to 5-(3) Bendability) and other methods can be applied. Further, since large spring back is likely to occur, there are cases where adjustment of the bending angles is required.

(3) An excessively small bending flange width results in the misalignment of the upper and lower steel sheets. Thus, sufficient flange width should be adopted.

(4) Roll-forming involves increased spring back, thus necessitating adjustment. In general, the greater the number of rolls, the better the forming finish.

(5) Punching is more advantageous than drilling. In applying either of these methods, care should be taken to avoid peeling off the visco-elastic resin layer, which is caused by hooking the upper sheet of VIBLESS during blanking. Further, punching or drilling should be done after fabrication.

❸ Joining (1) Resistance welding: The provision of a bypass circuit is required for the commercial grade (refer to paragraph 5-(5) Resistance Weldability).

(2) Arc welding: Because the resin is likely to burn and voids are likely to occur, care should be taken to adopt low heat input (refer to paragraph 5-(6) Arc Welding). There is also a method by which arc welding is performed after the visco-elastic resin has been removed by burning.

(3) Caulking: Even if the upper and lower sheets are misaligned, there should be no problem(4) Screw-fastening: Screws compatible with the upper and lower steel sheets should be used.

❹ Painting (1) For a high-temperature baking finish (180˚C or higher), the thermosetting resin type is essential, so please consult us prior to the application.

(2) The application of usual degreasing or chemical treatments poses no problem.

❺ Galvanizing at Fabricators’ Shop

(1) Electrogalvanizing: As for the commercial grade, the electric current should be passed through both surfaces.(2) Hot-dip galvanizing: It is recommended not to apply hot-dip galvanizing, because it changes the quality of the

visco-elastic resin.

❻ Treatment at Fabricators’ Shops

(1) Because VIBLESS is manufactured by bonding two steel sheets together, its rigidity is lower than that of an ordinary steel sheet having the same thickness. Accordingly, care should be exercised when

VIBLESS is used for members requiring structural strength.(2) Because the adhesive strength of visco-elastic resin is less than 1/10 that of ordinary steel sheets,

applications where force is applied in the direction that would cause delamination of steel sheets should be avoided.

(3) The properties of VIBLESS depend on the resin applied, so please consult us prior to the application planning.

14 15

VIBLESS Production Line Methods for Measuring Vibration-damping Capacity

Methods for Measuring Adhesive Strength

References

Layout of Coil Production Line Methods for Measuring Vibration-damping Capacity, Loss Factor η

No.1 Payoff Reel

Tension Reel

No.2 Payoff Reel

Resin Drying Furnace

Drying Furnace

No.1 Entry Loop Car

No. 2 Entry Loop Car

Steel Sheet Preheating Furnace

Drying FurnaceCooling Section

Exit Loop Car

Pressure-bonding Roll

Resin Coating Unit

Pretreating Unit

● NIPPON STEEL operates a VIBLESS production line exclusively for cut-sheet manufacture, in addition to the coil production line.

Measuring Method Principle of Measurement

Center-support Stationary Excitation Method

(Refer to the Figure Below)

The loss factor is obtainable from the half power band width (3 dB) of the frequency-response curve of the vibration acceleration divided by the excitation force.

η＝f2 - f1

f0

3 dB

A/F

f1 f0 f2

Center-support Stationary Excitation Method

F

A

F : Excitation ForceA : Acceleration

Thermostat

Test Piece

Exciter

Test Piece Width : 30 mm, Length : 300 mm

Impedance Head

Computers

Frequency Response Curve

FFTAnalyzer

Amplifier

Amplifier

Amplifier

❶ Shear Adhesive Strength

Room temperatureShear adhesive strength is obtained by calculating strength per 1 cm2 of area.

Test Piece Width : 25 mm

Weld Zone Length 10 mm

Steel Sheets

Resin

Tensile Speed5～50 (mm/min)

10 20 30 40

Displacement （mm）

T-p

eel l

oad

（kg

f）

20

0

40

60Test Piece Width : 25 mm

Room Temperature

Tensile Speed200 (mm/min)

10 20Displacement (mm)

T-p

eel L

oad

(kgf

)

20

0

40

60

T-peel Strength

30 40

❷ T-peel Strength

16 17

MEMO