7/24/2019 Smtc 5 110 008_2012 _

1/18

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

"#$%&'()*+,-./0123

Enterprise Standard of SAIC MOTOR Technical Center

SMT

SMTC 5 110 008

2012

V2"

!SMTC 5 110 0082011 (V1)

"/"#$%&'(&)

Hot-dip zinc/zinc-iron alloy coated steel sheet and strip

2012- 06-06 !/Issue 2012-06-07 "#/Implementation

"$%,-./,-234567

Technical Standardization Committee of SAIC MOTOR Technical Center

!

Issue

7/24/2019 Smtc 5 110 008_2012 _

2/18

SMTC 5 110 008

2012

V2"

I

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

$ %/Contents

"# Forward ......................................................................................... II1 $% Scope .......................................................................................... 12 &$'()*+ Normative reference .................................................................. 13 ,-./0 Terms and definitions .................................................................... 24 12.3 Classification and symbol ................................................................ 34.1 4512 Classification of steel sheet ............................................................ 34.2 63/0&7 Regulation of specification .......................................................... 45 8,9: Technical requirement ...................................................................... 45.1 ;

7/24/2019 Smtc 5 110 008_2012 _

3/18

SMTC 5 110 008

2012

V2"

II

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

& '

-&$ SMTC.B///0IJ45M12&3)456/7YZ8

9:;%*+M?@?ATBC4D

EFG^HIJKL=BCMMN8

%YZO+ SMTC 5 110 008-2011(V1)

P.B///0IJ45T4QRM}S8T%

YZUVWXY! SMTC 5 110 008-2011

(V1)8

%YZ& SMTC 5 110 008-2011(V1))m

MZ9l;O[

\\]v^ 5.3.4ntuvwx'M8,9

:p8

_`a*bcd0e4f`*-Z8

%YZM A-&$'4 B-#

$'8

%YZgh$1Yijk8

%YZg SMTC8,YZ;ilmnZ8

%YZgYZ;wopqrsO8

%YZYtuv[@wu8

%YZZ9Ytx[yzc{||}8

%YZ~20120105X!unZ"#4

2012 01 06XUV8%u-$%u}S8

%YZ&!YZM'u(%"#)*-[

\\SMTC 5 110 008-2011 (V1)8

Foreword

This standard is established for the design

and use of hot-dip zinc/zinc-iron alloy coatedsteel sheet of SMTC.

Please note that some contents in thisdocument may relate to patent rights, whichSAIC Group shall not be held responsible foridentifying any or all such patent rights.

This standard is a revision for SMTC 5 110008-2011(V1) Hot-dip zinc / zinc-iron alloycoated steel sheet and strip. This standard willreplace SMTC 5 110 008-2011(V1) from theimplementation date of it.

Comparing this standard with SMTC 5 110008-2011(V1), the main changes are as

follows:Section 5.3.4 added (The requirementof secondary working embrittlement).

This standard is in Chinese and English. Ifin doubt, the Chinese version is the Master.

Annex A is normative, Annex B isinformative.

This standard was proposed by thematerial sub-committee.

This standard was approved by the SMTCTechnical Standardization Committee.

This standard is under the management ofStandardization working team.

The drafting department of this standard

is: Quality Assurance Dept.The main drafters of this standard are: Fu

Yusheng, Diao Faxi.This standard was first published on Jan.

05, 2012 and implemented on Jan. 06, 2012.This revision is the first revision.

The issued case of all previous editions ofthe standards which was repaced by thisstandard:\SMTC 5 110 008-2011 (V1).

7/24/2019 Smtc 5 110 008_2012 _

4/18

SMTC 5 110 008

2012

V2"

1

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

()*/*+,-./0.1

Hot-dip zinc/zinc-iron alloycoated steel sheet and

strip

1 23

%YZ&/^.B///0IJ45T4QM,-./0{12.3{PQ{RS{8,9

:.ef+8

%YZ,)~DEFG-)./0cbM.

1`3)Mf2344Q-5546738.B

w9cbM.B///0IJ45T4Q4f:;

?67%YZM()@=-

%YZM>?8AO:XBM()*+4'CD

&EM}FGn^HIJKM>?pL}S(M

^,)~%YZ4N@4OPQR%YZS=T

UMVaWXOY@3)L=*+MZ[(%8

AO^:XBM()*+4'Z[(%,)~%

YZ8

GB/T 222-2006 4M=\;

7/24/2019 Smtc 5 110 008_2012 _

5/18

SMTC 5 110 008

2012

V2"

2

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

GB/T 20125-2006 gIJ4 "#fxAM

{/ ${%I+&l'kl"mno|

GB/T 20126-2006 (IJ4 gexAM{

/ $2 u1[{k|n)*v.p>}~D

R!|

GB/T 20564.1-2007 E.)y+L2344

5T4Q$1u1[yzq;4

GB/T 24173-2009 45tuvwx;efa

|

combustion in an induction furnace (routinemethod)

GB/T 20125-2006 Low-alloy steel -Determination of multi-element contents -Inductively coupled plasma atomic emissionspectrometric method

GB/T 20126-2006 Unalloyed steel -

Determination of low carbon content - Part 2:Infrared absorption method after combustionin an induction furnace (with preheating)

GB/T 20564.1-2007 Continuously coldrolled high strength steel sheet and strip forautomobile - Part 1: Bake hardening steel

GB/T 24173-2009 Steel sheets -Secondary work embrittlement testingmethod

3 9:;>.B/cb,D42

)7*NOM4Q34.//0`&56MB

C8.//0`/xAk^1~ 99%8CD467

IJ;NOw9789BCDS=/0IJC4

IJBC`0xA6p- 7:15%8

Hot dip zinc-iron alloy coating(ZF)(

(Application of a zinc coating by immersing

the prepared products in a molten bathcontaining a zinc content of at least 99%.Subsequent annealing produces an iron-zinccoating with an iron content of normally 7%to 15%.

,-./01>>;ge

4`v4,AM?L@434`Me{A67I64`M;

>7ge4L>ge4

`467G%LYI[v@4?4\+MIJ#

f4S=e

A;I

F]lgk^_+

;4`e467MIJ#fMa;b]o)4fc5dyM

+L8

High strength low alloy steel(HSLA)(

(Steel achieves the required strength level

primarily by adding small amounts ofmicro-alloying elements such as niobium,titanium and/or vanadium, which contributeto fine carbide/nitride precipitation and grainsize refining.

67892341>>7ge4L>ge4

`we%/AMELekl4f9e@67[v

g+EL+;#fJjy+L445=SD)h

iyzNO'+Lm^%jjy4`eLO45

kQEdSM=S'?8

Bake hardening high strength steel(

(An adequate amount of solid solution

carbon and/or nitrogen remains in the lowcarbon steel or ultra low carbon steel, solidsolution strengthening elements such asphosphorus, etc. may also be added to

7/24/2019 Smtc 5 110 008_2012 _

6/18

SMTC 5 110 008

2012

V2"

3

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

increase strength. The steel exhibits anadditional increase in yield strength due toage hardening after forming which isaccelerated by subsequent paint baking.Meanwhile, it has good formability.

:;1>>4MlMpmZ9-0f'.n

o'4no'pmfpqrs1#70f'5'

D8t)4;eu4QEgMv+m.dyMvwq;rsfTyzq;o4OGH2w+!x

h$W%8

Dual phase high strength steel((

Steel with both higher strength and

enhanced formability, consists of a ferriticmatrix containing a hard martensitic secondphase in the form of islands. Dual phasesteel does not age. It has a low yield ratio,high work-hardening index and bake -hardening value. It is good for structuralparts.

>4MlMpmZ9-0f'.

nLpyo'pm870f'.nLpyo'5

'D46p1#zAMno'{{|}o'.~

n'pm867[vMIJ#f TiL Nb4S=a

;b]Lgk+;Muk8LO4QE(pyM

h+L8&`+h+LMt)4)m4'v

+L!l9y""8LO4QEdyM?A

!?>.dyM{|kl?>8

Complex-phase high strength steel(

(Steel consists mainly of a ferrite and/or

bainite. Small amounts of martensite,austenite and pearlite remain in thesubstrate. By adding Ti or Nb, it can increasestrength. This kind of steel has a high tensile

strength. Its yield strength is higher thanwhat is the same tensile strength as it. It hashigh energy absorbing property and highresidual strain ability.

;=>?@A1>>4MlMpm-0f

'{yo'.{|}o'4'`4{|}o'M

xAZz^g~ 5%87=S7K`4{|}o'

@)l-no'pm4QEdyMvwq;#{

M$i]#.h+L8&`+h+LMt)

4)m4QE%yM&i#8

Transformation induced plasticity

steel(TRIP)((Steel consists mainly of a

ferrite, bainite and remainder austenite.Austenite is not lower than 5%. In theforming process, remainder austenite cantransform to martensite. This has a high workhardening rate, uniform elongation andtensile strength. Compared with the sametensile strength dual phase steel, it is higher

elongation.BCD=E>>2vw=S7K`4g~e

uMk'445k(^M$lS4)*45"c

+uj'lS4Z,m745EF-(&hia

.=%//LM%0=__,qM12L^&7

3,{^&7EF45+E6EFRN@AM7

88

Stretcher strain marks((As aging

during the steel processing, there may beinhomogeneous deformation. It will result inpartly plastic deformation. Defects whichinfluence surface quality will appear. Thesedefects include paralled drapes, irregular foldline, and irregular surface distortion.

4 ?@;AB 4 classification and symbol

4.1 459):;1)/Commercialge?@A4

Low carbon Al-killed steel

SCG2+Z,SCG2+ZF WX)/Drawing

;VW)/Super deep drawing

7/24/2019 Smtc 5 110 008_2012 _

7/18

SMTC 5 110 008

2012

V2"

4

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

C 1n8p/Table 1DcontinuousE

63/Steel grades Z9):/Application 5=/Steel description

SCG180Y+Z, SCG180Y+ZF WX)LVW)/Drawing or deep drawing;)LWX)/Commercial or drawing

SCG260Y+Z, SCG260Y+ZF GH)L%>)/Structural or commercial

SCG180B+Z, SCG180B+ZF WX)/Drawing

yzq;4

Bake hardening high strengthsteel

SCG220B+Z, SCG220B+ZF %>)LWX)/Commercial or drawing

SCG260B+Z, SCG260B+ZF GH)L%>)/Structural or commercial

SCG300B+Z, SCG300B+ZF GH)/Structural

SCG260L+Z, SCG260L+ZF

GH+/Structural part

y+LgIJ4

High strength low alloy steel

SCG300L+Z, SCG300L+ZF

SCG340L+Z, SCG340L+ZF

SCG380L+Z, SCG380L+ZF GH+4v++/

Structural and reinforced partSCG420L+Z, SCG420L+ZF

SCG260D+Z, SCG260D+ZF GH+/Structural part

t)4Dual phase high strength

steel

SCG300D+Z, SCG300D+ZF

GH+4v++/Structural and reinforced part

SCG340D+Z, SCG340D+ZF

SCG420D+Z, SCG420D+ZF

SCG500D+Z, SCG500D+ZF

SCG600D+Z, SCG600D+ZF v++4BC+/Reinforced and crashresistant art

SCG380T+Z, SCG380T+ZFGH+4v++/Structural and reinforced part

)lD)j'4Transfomation induced

plasticity steelSCG420T+Z, SCG420T+ZF

SCG340C+Z, SCG340C+ZF GH+4v++/Structural and reinforced partY)4

Complex-phase highstrength steel

SCG500C+Z, SCG500C+ZF v++4BC+/Reinforced and crashresistant partSCG700C+Z, SCG700C+ZF

4.2 63/0&79 A&t84.2 Regulation of specification shall be asgiven in Annex A.

5 F9GH 5 Technical requirement

5.1 IJK? 5.1 Chemical composition

5.1.1 4555M;

7/24/2019 Smtc 5 110 008_2012 _

8/18

SMTC 5 110 008

2012

V2"

5

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

C2 /Table 2

63

Steel grade

BCGH

Coatingstructure

> 0.5 mm and "0.7 mm (minus 2 units).

c _b\[LR~1.5 mme4r90Z1&/o@Tg0.28

For thicknesses > 1.5 mm the r90-values are additionally lowered by 0.2.d _b\[L1~0.7 mme4r90Z1&/o@Tg0.24n90@Tg0.018

For thicknesses < 0.7 mm the r90-values are additionally lowered by 0.2, and the n90-values are additionllylowered by 0.01.

e eu'[45T6UB=XY47V9>'WX'?YZ[fD9:4S^bchikl\8

Aging property: mechinicail property of steel shall be satisfied with the requirement above and be freefrom stretcher strain marks within 6 months commencing from manufactured date.

C3 /Table 3

+L+]Strength

level(MPa)

63

Symbol

BCGH

Coatingstructure

>

7/24/2019 Smtc 5 110 008_2012 _

9/18

SMTC 5 110 008

2012

V2"

6

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

C3(8)/Table 3DcontinousE

+L+]Strength

level(MPa)

63

Symbol

BCGH

Coatingstructure

>

7/24/2019 Smtc 5 110 008_2012 _

10/18

SMTC 5 110 008

2012

V2"

7

!"#$%&' ()*+,-.) Copyright SAIC MOTOR Confidential

C3(8)/Table 3DcontinousE

+L+]

Strengthlevel

(MPa)

63

Symbol

BCGHCoatingstructure

> 0.5 mm and "0.7 mm (minus 2 units).c _b\-.B/0IJ45e4ODi]#Z1&/W@Tg2%4r90Z1&/o@Tg0.28

For ZF-coatings, the A80 values are lowered by 2 units and the r90-values are lowered by 0.2.d

_b\[LR~1.5mme4r90Z1&/o@Tg0.28For thicknesses > 1.5 mm the r90-values are additionally lowered by 0.2.e eu'[45T6UB=XY47V9>'WX'?YZ[fD9:4S^bchikl\8

Aging property: mechinicail property of steel shall be satisfied with the requirement above and be freefrom stretcher strain marks within 6 months commencing from manufactured date.

f eu'[45T6UB=XY47_9>'WX'?YZ[fD9:4S^bchikl\8

Aging property: mechinicail property of steel shall be satisfied with the requirement above and be freefrom stretcher strain marks within 3 months commencing from manufactured date.

5.3 ./NO 5.3 steel quality

5.3.1 45MEFkQE`SMg;'{ha

'{bc'4'EF@AkZ[E 4M&/8

5.3.1 Steel sheet surface shall be of goodphosphatization, coating, and corrosionresistance.The classification of surfacequality shall be as given in Table 4.

C4 /Table 4

3

Symbol5d/Character

,)w+

Applied part

B

dSM%F^5Eec=4f71$%>UVH7gMX\{hi{/jk\{gM

MEFl;784m%FnzkS6f:9:[EFUVE1ec={o={Q\{

1M;u+Interior

C

dSM%Ffp+7q^%js64r^?sthiDMRN@A4ukEM$`S

MBC4m%FnzkS6f:9:[EFUVE1ec={o={Q\{1M;