Cold Roll Steel

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COLD ROLLEDSTEEL SHEET


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Cold rolled steel sheets offer a variety of outstanding properties,

including easy formability and a smooth, clean surface, and

are used in automobiles, appliances, furniture, and many other

everyday items.

JFE Steel Corporation who holds ISO9001, QS-9000 and

ISO14001 certi cations, produces a full range of cold rolled

products for these and other applications. Because strict quality

requirements are now applied to meet the needs of improved

product functions, JFE has adopted an integrated quality control

system. Customer requirements are re ected in products from

the quality design stage in order to supply customers with the

optimum material for each application in a timely manner.

Based on a wealth of experience and an advanced production

system, JFE is continuing to develop new technologies and

products which meet the needs of the times.


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Cold rolled steel sheet Contents

Characteristics

Superior workability

JFEs cold rolled products have excellent formabilityand minimal deviation in mechanical properties

thanks to the companys accumulated technicalexpertise, newly constructed and modernizedfacilities and innovative technologies, and integratedquality control system extending from raw materialsto the nal product.

Superior surface quality and dimensional accuracyM o d e r n f a c i l i t i e s , a d v a n c e d o p e r a t i o n a ltechnologies, strict inspection, and integrated qualitycontrol ensure excellent surface quality. Dimensional

accuracy is guaranteed by an automatic thicknesscontrol system using advanced numerical models.

Wide range of product standardsJFE produces cold rolled products to meet a widerange of product standards, including JIS and otherpublic standards, as well as internal JFE standards.Products range from general use, including extradeep drawing quality and bake hardening sheets, tohigh strength sheets and sheets for enameling andother special applications.

Wide range of sizesT h e a v a i l a b l e s i z e r a n g eincludes thickness from 0.14mm

to 3.2 mm and width up to1,850mm.

Superior shapeA p p l y i n g t e n s i o n l e v e l e rensures superior strip atness.

Outstanding technical serviceTo meet the requirementsof diverse clients, JFE has

established a complete technicalservicing system with advisesclients on questions rangingfrom material properties toprocessing technologies.

Manufacturing process 2

Correspondence with JFE standards to public standards 4

Product Standards, Characteristics and Application 5

JFE Standards 8

Dimensional and shape tolerances 18

Available product size range 20

Surface nish and strip edge 24

Packaging and labeling 25

Remarks on product use and handling precautions / Instructions for ordering 26

(Appendix) Extracts from Japanese Industrial Standard (JIS) ( 1 ) 27

(Appendix) Extracts from Japanese Industrial Standard (JIS) ( 2 ) 28


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Blast furnace

L i m e s t o n e

C o

k e

I r o n o r e

Converter

Vacuum degasser

Reheating furnace

Continuous caster Scale breaker Rougher Finishing train

Pickling line Continuous cold strip mill

Electrolytic cleaning line

Box annealing

Open coil annealing

Cold rolled coil (As-rolled)

Skinpass mill

Continuous annealing line

Shearing line

Recoiling line

Cold rolledslit coil

Cold rolled coil

Cold rolled coil

Cold rolled sheet

Fully continuous cold strip mill Continuous annealing line

Skinpass mill

3

M a n u

f a c t u r i n g p r o c e s s

Manufacturing process

Cold rollingThe thickness accuracy of cold rolledproducts is determined by the coldrolling process. Rolling force and striptension are computer-controlled tominimize thickness deviations duringrolling, based on measurements ofthe strip thickness at the entry anddelivery sides of the mill.

AnnealingThe formability of products is determined by annealing.Because cold rolling signi cantly increases materialhardness, making forming dif cult, annealing is performedto improve ductility by inducing a recrystallized structurein the steel. As the annealing process, coils are piled andcovered by the box and annealed and this is called thebatch annealing. The other is the continuous annealingprocess, in which coils are continuously treated. JFEuses two annealing technologies, depending on productrequirements.JFE is among the worlds leaders in process technologyfor the continuous annealing line (CAL), and has alsoused the CAL to develop a wide range of new products,from 1500N/mm 2 high strength steel to non-aging extradeep drawing grade. JFEs advanced CALs are highlycomputerized and feature automatic quality assuranceequipment, such as an automatic surface inspection devicewhich was developed by JFE.

Skinpass rollingAnnealed coils are lightly rolled by the skinpass mill toprevent a defect called stretcher strain, improve strip shape,and adjust mechanical properties. Skinpass rolling is alsoused to produce dull nish and bright nish products.

FinishingAfter skinpass rolling, coils are processed at the recoilingline, where they are cut to produce product coils of thespeci ed weight, or at the shearing line, where they are cutto sheets of the speci ed dimensions. Product thickness,width, shape, and surface quality are inspected, andmechanical properties are tested using specimens taken atthe nishing line.

CleaningRolling oil on the cold rolled strip isburned off during annealing, whichis the next process after cold rolling.Other types of rolling oil are removedby electrolytic cleaning prior toannealing. In particular, electrolyticcleaning is used with products whichrequire a clean surface to ensure goodpaintability .


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C or r e

s p on

d en

c ewi t h

J F E

s t an

d ar d

s t o p u b l i c

s t an

d ar d

s

Correspondence with JFE standards to public standards

Classi cationJFE

standardJIS ASTM Others

Steel sheets for general usesJFE-CCJFE-CDJFE-CE

G3141 SPCCSPCDSPCE

A109A1008

BS 1449 Part 1DIN1623 -2BS EN 10130DIN EN 10130BS EN 10139DIN EN 10139

High strength steel sheets JFE-CA G3135 SPFCA980

A1008

Atmospheric corrosionresistance steel sheets

JFE-CCUP G3125 SPA-C A 606BS EN 10155DIN EN 10155

Corrosion resistancesteel sheets

JFE-ASA

Steel sheets forporcelain enameling

JFE-CPE G3133 SPP A 424BS EN 10209DIN EN 10209

Steel sheets forelectric wire sheath

JFE-HWD

Steel sheets for galvanizing JFE-HKT

Steel sheets without annealing JFE-CNA

Steel sheets in h igh temperatureatmosphere

JFE-CHCR


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P r o

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t S t a n

d a r d s ,

C h a r a c t e r i s t

i c s a n

d A p p

l i c a

t i o n

JFE Steel is producing wide range of products which have excellent characteristics based on thepublic standards like Japanese Industrial Standard(JIS) to original JFE standard, at the East JapanWorks (Chiba and Keihin plants) and the West Japan Works (Fukuyama and Kurashiki plants).

Product Standards, Characteristics and Application

Public Standard ProductsJFE Steel is producing products based on following public standards.

Japanese Industrial Standard (JIS)

The Japan Iron and Steel Federation Standard (JFS)

Classi cation Designation Characteristics and Application

G 3141Cold-reduced carbon steel sheets

and stripSPCC SPCC-T

SPCD SPCE SPCEN

Best suited for automobiles, electrical appliances, etc.due to wider workable ranges from commercial todeep drawing qualities.

G 3135Cold rolled high strength steel

sheets with improved formabilityfor automobile structure use

SPFCSPFC***YSPFC***H

Mainly used for automobiles due to high strength andimproved formability.

G 3125Superior atmospheric corrosion

resisting rolled steelsSPA-C

Best suited for rolling stock bodies or constructionsdue to superior atmospheric corrosion resistance.

Classi cation Designation Characteristics and Application

A 2001Cold rolled steel sheets for

automobile useJSC

Specifying cold rolled steel products for automobileuse (General use to high strength steel)


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C h a r a c

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t i c s a n

d A p p

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t i o n

JFE Standard ProductsJFE Steel is producing cold rolled steel sheets for general use, high strength steel sheets and cold rolledsteel sheets for special use based on JFE standards.

Cold rolled steel sheets for general use

Cold rolled high strength steel sheets

Classi cation Designation Pages Characteristics and Application

Commercial quality JFE-CC

8 9

JFE produces six grades of cold rolled soft steelproducts, ranging from commercial quality JFE-CC(equivalent to JIS-SPCC) to extra deep drawingquality JFE-CG, which is superior to JIS-SPCEN, andultra deep drawing quality JFE-CGX, which features

an extremely high plastic strain ratio (mean r-value).

JFE also produces two grades of bake handenable(BH) cold rolled steel products which have aincreased yield point during baking after painting.

Drawing quality JFE-CD

Deep drawing quality 1 JFE-CE

Deep drawing quality 2 JFE-CF

Extra deep drawing quality JFE-CG

Ultra deep drawing quality JFE-CGX

Bake hardenability quality JFE-CEH

Deep drawing qual i ty wi th bakehardenability

JFE-CGH

Cold rolled steel sheets for special use

Classi cation Designation PagesTensile Strength ( N/mm 2 )

Characteristics Application forautomobile340 370 390 440 490 540 590 780 980 1180 1370 1470

Commercial quality JFE-CA

10 13

Suitable for general processing like drawing or bending. Applying the water-quenching by acontinuous annealing process, maximum 1 ,470 N/mm 2 tensile strength is available.

StructureReinforce

Deep drawing qual i tywith bake hardenability JFE-CA

H Superior in deep drawability and bake-hardening. Suitable for outer parts of automobileswhich require anti-dent properties.

Outer panel

Drawing quality JFE-CA F Superior ductility and suitable to drawing application.Outer panelInner part

D eep dra win g q ua lit y J FE -C A P Having excellent ductility and high r-value, suitable materials for deep drawing. Outer panel

Inner part

E x t ra d e e p d ra wi n gquality JFE-CA

G Adding excellent r-value and ductility with attaining super ne grain structure, suitablematerials for extra deep drawing because of having good secondary-embrittlementresistance.

Outer panelInner part

High stretch angeformability quality JFE-CA

SF Having excellent ductility and high stretch ange formability, suitable for drawing with angeexpansion forming.

StructureReinforce

Low yield ratio qualitytype 1 JFE-CA

Y1 Having excellent ductility and high work hardening coef cient, suitable material for deepdrawing processing.

StructureReinforceLow yield ratio quality

type 2 JFE-CAY2

High e longat ion quali ty JFE-CA A Applying TRIP (Transformation Induced Plasticity) effects, excellent ductility and workhardening coef cient are achieved at the high strain range.

StructureReinforce

Classi cation Designation Pages Characteristics and Application

Cold rolled steel sheetsfor porcelain enameling JFE-CPE

14 Chemical compositions are adjusted for porcelain enameling use.General use or deep drawing, 1 -coat or 2 -coat usages are available.

Cold rolled steel sheetsfor electric wire sheath JFE-CWD

15 Products especially developed for electric wire sheathing. Superiorfor welding and working.

Cold rolled steel sheetsfor galvanizing JFE-CKT

15 Annealed cold-rolled sheet as the mother material for galvanizing isavailable.

Cold rolled steel sheetswithout annealing JFE-CNA

16 Non-annealed cold-rolled sheet of thinner gages are available.Suitable for application needed strength without forming.

Cold rolled corrosion

resistance steel sheetsJFE-ASA 16

Having superior resistance against sulfuric acid corrosion andatmospheric corrosion. Suitable to the air pre-heater of boilers, heatexchangers, chemical plants and exhaust chambers.

Cold rolled atmosphericcorrosion resistance high

strength steel sheetsJFE-CCUP 17 Having the superior corrosion resistance without painting due to thestable oxide lm. Suitable to rolling stock bodies and structures.

Cold rolled steel sheetsin high temperature

atmosphereJFE-CHCR 17

Having superior anti-oxidation properties and keeping strength underhigh temperature( 450 -600 C). Suitable to application like chimneyducts, needed heat resistance and workability.


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J F E S t a n

d a r d s

Mechanical Properties

Dimensional toleranceSize tolerances conform JIS G 3141(Cold-reduced carbon steel sheets and s trip). Refer to page 18.

Cold rolled steel sheets for general use JFE-CJFE produces six grades of cold rolled soft steel products, according to formability, ranging fromcommercial quality JFE-CC (equivalent to JIS-SPCC) to extra deep drawing quality JFE-CG, which issuperior to JIS-SPCEN, and ultra deep drawing quality JFE-CGX, which features an extremely highplastic strain ratio (mean r-value). JFE also produces two grades of bake- hardening (BH) cold rolledsheets, which display yield point increase when baked after painting. Ultra deep drawing

Extra deep drawing

Deep drawing 2

Deep drawing 1

Drawing

Thickness : 0.8mm

2.5

2.0

1.5

40 50 60Elongation (%)

A v e r a g e p

l a s t i c s t r a

i n r a

t i o

( M e a n r - v a l u e

) Extra deep drawing Ultra deep drawing

Available product size rangeThe available size range is shown on page 20.

Automobile part (Front fender) Automobile part (Side panel outer)

Relation between elongation and average plastic strain ratio(mean r-value) of cold rolled steel

Comparison of height of cups cylinder between extradeep drawing and ultra deep drawing quality

JFE Standards

Classi cation Designation

Tensile Test Mean r-value

min.BH Value

min.(N/mm 2 )

Yield Point min. (N/mm 2 )Tensile

Strengthmin.

(N/mm 2 )

Elongation min. (%)

Thickness mm Thickness mm Thickness mm

0 .4< 0 .8

0 .8< 1 .0

1.03 .2

0 .4< 0 .6

0 .6< 0 .8

0 .8< 1 .0

1.0< 1 .2

1 .2< 1.6

1 .6< 2 .0

2 .0< 2 .5

2 .53 .2

0 .51.0

1 .0

Cold Roll Steel

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