1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW15192 Aluminum Sheet for Body and Closure Panel Applications Copyright 2011 General Motors Company All Rights Reserved October 2011 Originating Department: North American Engineering Standards Page 1 of 17 1 Scope This standard covers the re
2、quirements for wrought aluminum alloy sheet for exposed and unexposed body and closure panel applications. This specification is applicable to two types of wrought aluminum alloys; age hardenable and non-age hardenable. Age hardenable (e.g., 6000 series) aluminum alloys can be used for exposed and u
3、nexposed applications. Due to surface characteristics, non-age hardenable (e.g., 5000 series) alloys may not be suitable for exposed applications. Age hardenable aluminum alloys attain an increase in strength due to strain hardening and accelerated aging (precipitation hardening) when subjected to t
4、he assembly plant paint bake cycle or other post-forming heat treatments. Non-age hardenable aluminum alloys increase in strength due to strain hardening only, and will show some decrease in strength following the paint bake cycle or other post-forming heat treatment. Additional requirements or agre
5、ements shall be specified by each region (e.g., General Motors North America (GMNA), General Motors Europe (GME), General Motors Latin America, Africa and Middle East (GMLAAM), General Motors Asia Pacific (GMAP), etc.) 1.1 Material Description. For closure panel applications, the material designatio
6、n is defined by the GMW base metal specification number, basic aluminum alloy concept (5000 or 6000), special processing category, minimum as received yield strength and finish type. For body structure applications, the material designation is defined by the GMW base metal specification number, basi
7、c aluminum alloy concept (5000 or 6000), special processing category, minimum as received yield strength and minimum yield strength after typical T6 heat treatment. For specific material call-outs see Section 8. Examples of Aluminum Association (AA) alloys, European Standard Aluminum Wrought (EN AW)
8、 alloys and Japanese Industrial Standards (JIS) alloys are shown in Table 1. 1.2 Symbols. Not applicable. 1.3 Typical Applications. Typical applications include body and closure panel applications such as hoods, doors, fenders, liftgates, bodysides, roofs, and underbody components. 2 References Note
9、: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM E34 ASTM E607 JIS H4000 ISO 10275 ASTM E101 ASTM E1251 ISO 6892 ISO/TS 16949 ASTM E517 EN 573 ISO 10113 SAE J911 2.2 GM Standards/Specifications. GM6180M GMW3059 GMW15420 GMW2
10、GMW3335 GMW15421 GMW3011 GMW14019 GMW16549 2.3 Additional References. Manufacturing Engineering (ME) Lastenheft TMC003 Material Safety Data Sheet guidance documents (available at ). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEE
11、RING STANDARDS GMW15192 Copyright 2011 General Motors Company All Rights Reserved October 2011 Page 2 of 17 3 Requirements 3.1 Requirements on Test Specimens. Reference GMW15420. 3.1.1 Special Processing Requirements. S Standard IBR Improved Bake Response IH Improved Hemming HS High Strength RSS Red
12、uce Stretcher Strain ST Structural Parts R Reinforcement Parts 3.2 Requirements on Delivery. The following section defines specific requirements for material on delivery, processing, performance and other stages during life cycle. Deviations required for regional GM business units are listed in the
13、Deviations Section at the end of this specification. In case of dispute, the GMW15192 specification shall take precedence. 3.2.1 Chemical Requirements. 3.2.1.1 Base Metal. Base metal composition shall conform to the requirements of Table 2. Additional demands and restrictions may be imposed by regio
14、nal Materials Engineering organizations depending upon the application. The base metal chemical composition shall be determined per ASTM E34, ASTM E101, ASTM E607, ASTM E1251 or EN 573. In cases of dispute, referee method shall be ASTM E34. 3.2.1.2 Surface Treatment. All aluminum sheet should have a
15、 mill applied corrosion preventative lubricant. Mill oils, prelubes, hot melts, etc., applied to the material by the aluminum mill and the parts manufacturer must be removable in the purchasers phosphate cleaner system. Mill-applied products must be approved to GMW14019 and/or approved by the region
16、al business unit. 3.2.2 Mechanical Requirements. 3.2.2.1 Tensile Mechanical Property Requirements. The aluminum products shall meet the mechanical properties as specified in Tables 3, 4, 5, and 6. The 0.2% Offset Yield Strength, Ultimate Tensile Strength, Percent Uniform Elongation, and Percent Tota
17、l Elongation shall be determined in the transverse direction per GMW3335. For flat products with widths 300 mm, test samples in rolling direction are allowed. Tests shall be performed using samples per ISO 6892 Type I (50 mm gage length ASTM type sample) or ISO 6892 Type II (80 mm gage length DIN ty
18、pe sample). Strain hardening exponent n shall be determined per ISO 10275. The specific strain level shall be reported with all test results. Strain hardening exponent n shall be determined at 10% to 20% strain or from 10% to the end of uniform elongation if the uniform elongation is less than 20%.
19、The plastic strain ratio, r-value, shall be determined at 10% strain per ISO 10113 or ASTM E517. The mechanical property requirements shown in Table 3 shall represent material that has naturally aged a minimum of (3) days following Solution Heat Treatment (SHT). For production material, required mec
20、hanical properties shall be guaranteed for a minimum of 3 months after delivery to a GM Manufacturing Plant. For material qualification, required mechanical properties shall be guaranteed for a minimum of 6 months after SHT. The mechanical property requirements shown in Table 4 shall be guaranteed f
21、or material that has been through a simulated paint bake cycle of 185 C for 20 minutes. Table A1 in Appendix A shows typical yield strength ranges for different paint bake cycles, based on primer type and after 2% prestrain. Figure A1 shows the different paint bake cycles. Note that information in A
22、ppendix A is for GM Engineering Information Only. The information in Appendix A is not guaranteed by the supplier. The mechanical property requirements shown in Table 5 shall be guaranteed for material that has been through a typical T6 heat treatment. A typical T6 heat treatment is 205 C for 1 hour
23、. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15192 Copyright 2011 General Motors Company All Rights Reserved October 2011 Page 3 of 17 3.2.2.2 Hemming Requirements. All aluminum products for exposed applicat
24、ions shall meet the hemming requirements as specified in Table 6, in both the longitudinal 0 degrees and transverse 90 degrees directions. For production material, the hemming factor shall be guaranteed for a minimum of 3 months after delivery to a GM Manufacturing Plant. For material qualification,
25、 the hemming factor shall be guaranteed for a minimum of six months after SHT. The hemming factor is defined as: Where: ri = punch radius t = sheet thickness, as seen in Figure 1 The hemming factor shall be determined using GMW15421, and represents the minimum radius above which the hem surface has
26、good quality as defined by GMW15421, with no cracks or micro cracks. 3.2.3 Physical Requirements. 3.2.3.1 Material Thickness and Tolerance. The detailed engineering part drawing/electronic math file will specify the material thickness and tolerance. The sheet thickness tolerance requirements are lis
27、ted in Table 7. The tolerance requirements shall be referenced as follows: Thickness Tolerance: Per GMW15192. 3.2.3.2 Surface Requirements. 3.2.3.2.1 Surface Condition. Specific surface condition requirements for each region are detailed in the Deviations Section at the end of this document. 3.2.3.2
28、.2 Surface Quality. For unexposed (U) surface, defects such as pores, slight indentations, small marks, minor scratches, and slight coloring, which do not affect formability or the application of surface coatings, are allowed. Exposed (E) surfaces shall be free of defects which might affect the unif
29、orm appearance of a quality paint coating or a cathodic electrodeposition primer (E-coat, ELPO, Electro coat, or an electrolytic coating). The other surface shall conform at least to unexposed (U) surface quality. Certain applications may require both surfaces of the aluminum sheet to conform to exp
30、osed (E) surface quality. 3.2.3.2.3 Surface Texture. Specific surface texture requirements for each region are detailed in the Deviations Section at the end of this document. 3.2.3.2.4 Surface Appearance after Straining Tension Perpendicular to Rolling Direction. Age hardenable aluminum alloy sheet
31、approved to this specification for exposed (E) applications shall be free from surface irregularities commonly known as “paint brush” or “roping” lines which form on the surface of the sheet upon application of tensile strain perpendicular to the sheet rolling direction. The evaluation method is def
32、ined in GMW15420. Supplier shall submit test samples to show proof of conformance. 3.2.3.2.5 Compatibility with Phosphate and Paint Systems. For painted applications, the surface shall be capable of achieving a high quality zinc phosphate conversion coating using materials and processing information
33、 specified in GMW3011. The phosphate layer shall be homogeneous, continuous, and cover 100% of the surface. Aluminum sheet supplied to this specification must have a surface treatment according to paragraph 3.2.1.2, and must meet phosphate compatibility and paint appearance requirements according to
34、 GMW3011 and GMW15420. 3.2.3.2.6 Adhesive Compatibility. The aluminum alloy sheet approved to this specification shall be tested according to GMW16549. The qualification champion has the responsibility to determine the extensiveness of testing. 3.2.3.2.7 Reduced Stretcher Strain Alloys. Reduced Stre
35、tcher Strain (RSS) alloys shall be free from surface irregularities commonly known as “stretcher strain marks” or “Lders lines”. Yield Point Elongation (YPE) shall be measured using the sample geometry defined in GMW3335. Tensile testing shall be in both the longitudinal 0 degrees and transverse 90
36、degrees directions on samples from three (3) different coils. After tensile testing, enlarge the tensile curve graphically so that the strain path between 0% and 1.5% and the full YPE domain are clearly visible. The YPE plateau is defined as the area between the first peak on the Provided by IHSNot
37、for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW15192 Copyright 2011 General Motors Company All Rights Reserved October 2011 Page 4 of 17 stress strain curve and the end of the plateau. Measure the YPE and express it as a percentag
38、e with two decimal places. The YPE must be less than 0.60% for the alloy to be classified as a reduced stretcher strain. 3.2.3.2.8 Base Metal Density Values. For theoretical calculation of product and part mass, the base metal densities shown in Table A2 shall be used. Note that information in Appen
39、dix A is for GM Engineering Information Only. The information in Appendix A is not guaranteed by the supplier. 3.2.3.2.9 Base Metal Thermal Expansion Coefficient Values. For thermal calculations, the thermal expansion coefficients shown in Table A3 shall be used. Note that information in Appendix A
40、is for GM Engineering Information Only. The information in Appendix A is not guaranteed by the supplier. 3.2.4 Additional Requirements. 3.2.4.1 Lot Identification. All shipments of production age-hardenable aluminum alloy sheet, blanks or coils shall show date (month, day and year) of SHT and quench
41、ing at suppliers production facility on the suppliers material certification warrant. All shipments of production non-age hardenable aluminum alloy shall show the production date on the suppliers material certification warrant. 3.2.4.2 Other Requirements. Requirements such as tolerances on product s
42、hape and dimensions, inspection units, number of tests, sampling, test conditions, re-tests, inspection documents, packing, and handling of disputes shall be agreed upon between supplier and the regional business unit. 3.3 Joining. The aluminum sheet products supplied to this standard shall be suita
43、ble for mechanical clinching and welding by standard methods. 3.4 Performance Requirements. Not applicable. 3.5 Requirements on Other Stages During Life Cycle. 3.5.1 Chemical Requirements. Provisions shall be made to prevent the addition of such elements (see 5.3) from scrap or other materials used
44、in the manufacturing process which would impair the recyclability of the finished components. 3.5.2 Mechanical Requirements. Not applicable. 3.5.3 Physical Requirements. Not applicable. 3.5.4 Additional Requirements. Not applicable. 4 Manufacturing Process Not applicable. 5 Rules and Regulations 5.1
45、 Legal Regulations. All materials must satisfy applicable laws, rules, regulations and recommendations valid in the country of usage. 5.2 Language. In the event of conflict between the English and domestic language, the English language shall take precedence. 5.3 Inspection and Rejection. Samples of
46、 components or materials released to a GM material specification shall be tested for conformity with the requirements of this material specification and approved by the responsible Engineering department prior to commencement of delivery of bulk supplies. A new approval must be received for any chan
47、ges, e.g., properties, manufacturing process, location of manufacture, etc. If not otherwise agreed, all testing and documentation normally required for initial release must be completed. It is the responsibility of the supplier to inform the customer in a timely manner, without solicitation, and to
48、 include documentation of all modifications of materials and/or processes and to apply for a new release. If not otherwise agreed, all release tests shall be repeated and documented by the supplier prior to commencement of delivery of non-conforming bulk supplies. In individual cases, a shorter test
49、 can be agreed to between the responsible Engineering department and the supplier. 5.4 Initial Source Approval. No shipments shall be made by any supplier until representative initial production samples have been approved by the appropriate Materials Engineering department(s) as meeting the requirements of this specification. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM
