1、WORLDWIDEENGINEERINGSTANDARDSMaterial Specification GMW3032High Strength Sheet Steel, 180 MPa through 700 MPa Yield Strengths Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Originating Department: GME Specification Center Page 1 of 231 ScopeThis standard covers the requirement
2、s for continuous cast sheet steel with specified minimum yield strengthsfrom 180 MPa through 700 MPa and is applicable to uncoated and coated, cold (CR) or hot rolled (HR) lowcarbon, solid solution strengthened, bake-hardenable (BH), and interstitial free (IF) or high strength low alloy(HSLA) substr
3、ates with good formability. Continuously hot or cold rolled flat products shall be supplied as coilsor sheet. Hot rolled flat products are usually supplied in thicknesses 1.75 mm. These flat products are usedfor cold forming and for manufacturing of welded tubes. Cold or hot rolled flat products wit
4、h the appropriatesurface type and surface finish are suitable for the application of surface coatings (metallic hot dipping,electrolytic plating, hot spray painting, organic coatings and/or other coatings). This specification does notapply to steel for case hardening and cold reduced, work hardened
5、strips. Additional requirements oragreements shall be specified by regional GM business units, e.g., North America (GMNA), Europe (GME),Latin America (GMLAAM), and Asia Pacific (GMAP).1.1 Material Description. The material designation is defined by the GMW base metal specification number,steel produ
6、ct type, minimum yield strength, and finish type. The steel product type is designated by CR for coldrolled products, or HR for hot rolled products. Microstructure free of banding, which is caused by theinterdendritic segregation of manganese during solidification, is specified for hot rolled HSLA i
7、nclusion-controlled grades that are used for chassis applications.A numeral (180, 210, 240, etc.) will designate the minimum yield strength level in MPa (Mega-Pascals). Adesignation of steel type shall be added to bake hardenable (B2), solid solution strengthened grades (P andIF), structural automot
8、ive (SA) and high strength low alloy (LA) steels as shown in paragraph 8. An “F”designation may be added on engineering and/or manufacturing documents following an LA steel type tospecify the steel as inclusion-controlled. A “B” designation is specified for hot rolled LAF type grades whichneed to be
9、 free of microstructural banding. The steel grades will correspond to the chemical and mechanicalrequirements as shown in Tables 1 thru 5. The finish type, Pan alpha character, will designate the finish as E(exposed) or U (unexposed). In addition, products which are not coated shall have the word “U
10、NCOATED”added to the call-out after the steel type, but before the finish designation. A special requirement for temperrolling may be required and shall be specified with a “T” designation. The above descriptive items are usedtogether to form the coding system. Examples of the coding system for engi
11、neering part drawings andmanufacturing engineering documents are shown in paragraph 8.1.1.1 Material Identification. See Appendix A.1.2 Symbols. Not applicable.1.3 Typical Applications. Typical applications are coated or uncoated sheet metal parts consisting of highstrength sheet steel with specifie
12、d minimum yield strengths from 180 MPa through 700 MPa.2 ReferencesNote: Only the latest approved standards are applicable unless otherwise specified.2.1 External Standards/Specifications.AS 1391 ASTM E45 ISO 14284 JIS Z 2201ASTM A751 ASTM A370 ISO 6892ASTM E112 EN 10049 ISO 7438ASTM E1268 EN 10247
13、JIS G 3113Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page
14、 2 of 232.2 GM Standards/Specifications.GM6180M GMW3224 GMW14704 GMW15425GMW8 GMW3335 GMW14729 GMW16066GMW11 GMW14019 GMW14829 GMW16086GMW3005 GMW14057 GMW14872 GMW16170GMW3011 GMW14058 GMW15056 GMW16549GMW3059 GMW14700 GMW15282 GMW168232.3 Additional References.TMC003 Material Safety Data Sheet gui
15、dance documents (available at ).GWS-5A3 RequirementsThe following section defines specific requirements for material on delivery, processing, performance and otherstages during life cycle. Deviations required for individual GM business units are listed in the Deviation sectionand shall be agreed bet
16、ween Purchasing and supplier.3.1 Requirements on Test Specimens. Not applicable.3.2 Requirements on Delivery.3.2.1 Chemical Requirements.3.2.1.1 Base Metal. Base metal composition based on product (coil or sheet/blanks) analysis determined perASTM A751 shall conform to the requirements of Tables 1 a
17、nd 2. When end-product (coil/blank) test resultsare not available, heat analysis may be used. Chemical composition on the end product is the referee method.3.2.1.2 Surface Treatment. Products coated with a designated lubricant (e.g., mill oil or pre-lube) shall complywith GMW14019.3.2.2 Mechanical R
18、equirements. Products supplied to this specification shall meet the mechanical propertiesas specified in Tables 3 thru 6. The mechanical test methods to be used are defined in GMW3335 using theappropriate tensile test piece required by the specific region. Tests shall be performed using samples perI
19、SO 6892 Type I (50 mm gage length ASTM type sample), ISO 6892 Type II (80 mm gage length DIN typesample) or JIS Z 2201 (#5). Plastic strain ratio r (r-bar) shall be determined at 20 % strain. When uniformelongation is 0.5 mm, the minimum value for elongation is reduced by 2 units. For thickness 0.5
20、mm, the minimum value is reduced by 4 units.Note 4: ZnNi and Galvanneal coated steels: rm (r-bar) shall be reduced by 0.1; n value to be reduced by 0.01; total elongation to be reduced by 2 %.Note 5: For thickness 1.6 mm, the minimum r-value requirement will be 1.0.Note 6: Calculation by (r0+r90+2r4
21、5)/4.Note 7: The BH2 index requirement in this specification is used to characterize the general bake hardening response of steel. For vehicle design, the actual processing conditions (temperaturecycle, pre-straining, etc.) shall be considered.Note 8: Valid only for GMECopyright General Motors Compa
22、ny Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page 17 of 23Table 4: Cold Rolled High Stren
23、gth Low Alloy GradesMechanical Property Requirements Note 1GMW-3032M-ST-S Yield StrengthNote 3in MPaTensileStrengthin MPaTotalElongation50 mmin %TotalElongation80 mmin %TotalElongation(JIS #5)50 mmin %n-valueNote 4Designation Min. Max. Min. Min. Min. Min. Min.CR240LA 240 320 320 28 26 32 0.15CR270LA
24、 270 350 330 26 24 30 0.15CR300LA 300 380 370 24 22 28 0.14CR340LA 340 420 410 22 20 26 0.13CR380LA 380 460 450 20 18 24 0.12CR420LA 420 520 480 18 16 22 0.11 Note 3CR500LA 500 600 560 16 14 20 0.09 Note 3Note 1: Additional demands can be specified by local units.Note 2: The yield stress values shal
25、l apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise thevalues shall be the lower yield stress, ReL.Note 3: n-value tested from 6 % to end of uniform elongation.Note 4: ZnNi and Galvanneal coated steels: n value to be reduced by 0.01.Table 5: Hot Rolle
26、d High Strength Low Alloy GradesMechanical Property Requirements Note 1GMW3032M-ST-S Yield StrengthNote 2, Note 3in MPaTensileStrengthNote 2in MPaTotalElongation50 mmin %TotalElongation80 mmin % Note 2TotalElongation(JIS #5)50 mmin %n-value Note 4Designation Min. Max. Min. Min. Min. Min. Min.HR240LA
27、 240 320 290 31 29 35 0.16HR270LA 270 350 330 29 27 33 0.15HR300LA 300 380 370 27 25 31 0.14HR340LA 340 420 410 25 23 29 0.13HR380LA 380 460 450 23 21 27 0.12HR420LA 420 520 480 22 20 26 0.11 Note 5HR500LA 500 600 560 20 18 24 0.09 Note 5HR550LA Note 6 550 650 610 18 16 22 0.08 Note 5HR650LA Note 6
28、650 780 700 14 12 20 0.07 Note 5HR700LA Note 6 700 850 750 12 10 18 0.06 Note 5Note 1: Additional demands can be specified by local units.Note 2: The values stated apply to product thicknesses from (2 to 8) mm in the as-delivered condition. Higher or lower values of thicknessand other as delivered c
29、onditions may be agreed at the time of ordering.Note 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise thevalues shall be the lower yield stress, ReL.Note 4: Galvanneal coated steels shall be reduced by 0.01.Note 5: n-
30、value tested from 6 % to end of uniform elongation.Note 6: For hot-dipped zinc coated HR grades with YS 550 MPa, the minimum total elongation shall be reduced by 3 %. See deviationssection.Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo repr
31、oduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page 18 of 23Table 6: Hot Rolled Structural Automotive Grades (Intended for Chassis Applications) Mechanical Property Require
32、ments Note 1, Note 2GMW3032M-ST-STensileStrengthin MPaYield Strength Note 3Total Elongation (JIS #5)50 mmin %BendabilityThickness, tin mmThickness, tin mm BendAngleInside radiust 6.0 6.0 t 8.0 8.0 t 14.0 1.6 t 2.0 2.0 t 2.5 2.5 t 3.15 3.15 t 4.0 4.0 t 6.3 6.3 t 14.0Thickness, tin mmDesignation Min.
33、Min. Min. Min. Min. Min. Min. Min. Min. Min. 180 t 2.0 t 2.0HR370T-SA 370 225 225 215 32 33 35 36 37 25180t x 0.5 t x 1.0HR440T-SA 440 305 295 295 29 30 32 33 34 22 t x 1.0 t x 1.5Note 1: Additional demands can be specified by local units.Note 2: Test per ISO 7438 transverse to rolling direction.Not
34、e 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL.Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproductio
35、n or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page 19 of 23Appendix ATable A1: Structural Automotive GradesGM WORLDWIDE NORTH AMERICA EUROPE LATIN AMERICA ASIA PACIFICGMW3032M-ST
36、-S-HR370T-SA JIS G3113-SAPH370GMW3032M-ST-S-HR440T-SA JIS G3113-SAPPH440Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 20
37、13 General Motors Company All Rights ReservedJanuary 2013 Page 20 of 23Appendix BFigures B1 and B2 illustrate the definition of the Bake Hardening Index (BHI) and Work Hardening Index (WHI)on schematic diagrams of stress-strain curves. Graphical descriptions of the BH0 bake hardening indexdetermined
38、 at 0 % pre-strain (not pre-strained), and the BH2 bake hardening and work hardening indexesdetermined at 2 % pre-strain are shown on Figure B1 and Figure B2, respectively. The bake hardening indexfor bake hardenable steels shall be determined on specimens that are not pre-strained and 2 % pre-strai
39、nedand baked at +170 C for 20 minutes. Standard test specimens will be taken from unstrained and unbakedmaterial in the longitudinal (rolling) direction and tested per ISO 6892 or ASTM A370.Figure B1: Determination of Bake Hardening(No Pre-Strain)Figure B2: Determination of Bake Hardening andWork Ha
40、rdening Indexes (Pre-Strain)Note 1: The industry standard time and temperature to evaluate general bake hardenability of steel is +170 C for 20 minutes. Thisstandard is independent of the minimum time and temperatures required to effectively activate bake hardening. The GM standardminimum ELPO paint
41、 bake oven requirements of +160 C for 15 minutes for heavy metal sections is adequate to meet the intent of thebake hardening requirements of these steels.StrainBHo170C/20 minutes Note 1StressBH2WH = WorkHardeningStress170C/20 minutes Note 1WHStrain2%Pre-StrainCopyright General Motors Company Provid
42、ed by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page 21 of 23Appendix CWhen specified as a suffix let
43、ter B, the steel shall meet an Anisotropy Index, AI=2.0 level of microstructuralorientation according to ASTM E1268.Example:GMW3032M-ST-S-HR550LAF-B-Uncoated-UCopyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitt
44、ed without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW3032 Copyright 2013 General Motors Company All Rights ReservedJanuary 2013 Page 22 of 23DeviationsNote: Paragraph numbers may not appear sequentially, due to only those with deviations are included in thissection.Deviations on req
45、uirements for individual GM business units.In case of disputes or conflicts, the corresponding local standards and norms (North America, Europe, LatinAmerica, Asia Pacific) shall apply.Dev 3.2.1.1 Base Metal.GM Asia Pacific: Steel products shall have chemical composition which is agreed between purc
46、haser andsupplier which is capable of achieving the desired mechanical properties specified in GMW3032M-ST-S.GM North America: Maximum phosphorus content in Table 2 of 0.06 % is permissible with welding approval.All P grades with % C 0.015 must contain a minimum of 0.0003 % (3 ppm) boron or must hav
47、e a BH2 valueof 20 MPa minimum.GM Europe: The chemical composition of the base material in % by mass determined per ISO 14284 shallmeet the requirements listed in Table 1 and Table 2. The contents of unlisted elements are to the choice of theproducer as long as they do not affect the specified requi
48、rements and the production processes.Dev 3.2.1.2 Surface Treatment.GM Asia Pacific: For cold rolled and hot rolled steel supplied to this specification mill oils, shipping oils, pressoils, etc., applied to the material by the steel mill and the parts manufacturer must be removable in thepurchasers p
49、hosphate pre-cleaning system. The material must be capable of achieving an even phosphatecoating in the purchasers phosphate system. The phosphate coating weight and crystal morphology must beas expected for that type of sheet metal material phosphate coating in the purchasers phosphate system.Dev 3.2.2 Mechanical Require
