1、 WORLDWIDE ENGINEERING STANDARDS Material Specification GMW16866 Extruded Aluminum Mechanical Tubing and Hydroformed Components Copyright 2013 General Motors Company All Rights Reserved March 2013 Page 1 of 16 1 Scope 1.1 Material Description. This specification covers round extruded aluminum mechan
2、ical tubing and hydroformed components for vehicle body structure and chassis applications. For straight, hollow and semi-hollow aluminum extruded profiles produced from welding chamber (i.e., spider, porthole, or bridge) dies, solid aluminum extruded profiles, solid aluminum extruded round bars, an
3、d narrow flat aluminum extruded sheets, refer to GMW15665. 1.2 Symbols. Not applicable. 1.3 Typical Applications. Typical applications include, but not limited to, aluminum body structure side rails, aluminum body structure roof bows, chassis engine cradles, and chassis rear suspension cradles. 2 Re
4、ferences Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. ASTM B221M ASTM E34 ASTM E607 ISO 8493 ASTM B241 ASTM E101 ASTM E1251 SAE J911 2.2 GM Standards/Specifications. 9984309 GMW3059 GMW15665 GMW16549 GMW3011 GMW3335 GMW161
5、70 GMW16721 2.3 Additional References. Aluminum Association Aluminum Standards and Data Manual - Metric SI. Aluminum Association publication QCA-2, “Visual Quality Characteristics of Aluminum Extrusions”. General Motors Material Property Database. TMC003 Material Safety Data Sheet guidance documents
6、 (available at ). 3 Requirements 3.1 Requirements on Test Specimens. 3.1.1 Chemical Requirements. Tubing and hydroformed components furnished shall conform to the chemical composition (percentage by weight) in Table A1. Chemical composition shall be determined per ASTM E34, ASTM E101, or ASTM E1251.
7、 In cases of dispute, referee method shall be ASTM E34. 3.1.2 Mechanical Requirements. 3.1.2.1 Mechanical Property Requirements. Tubing and hydroformed components including longitudinal weld seams shall meet the mechanical property requirements shown in Table A2. The extrusion process at the tube su
8、pplier shall be adjusted to compensate for excess mechanical property variation if the mechanical properties of a single tube sample measured at the standard tensile sampling locations (see Figure A1) varies by more than 10% from the average value. Additionally, the longitudinal weld seams must have
9、 mechanical properties within 10% of the average value. Mechanical properties shall be determined per GMW3335. 3.1.2.2 Post-Paint Bake Mechanical Properties. Aluminum hydroformed components may show significant tensile mechanical properties changes following E-coat and paint (i.e., primer surfacer,
10、basecoat, topcoat) bake processing. Supplier may be required to modify aluminum hydroformed component artificial aging practice in order to assure that component exceeds minimum tensile mechanical property requirements after GM assembly plant E-coat and paint bake processing. Copyright General Motor
11、s Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16866 Copyright 2013 General Motors Company All Rights Reserved March 2013 Page 2 of 16 3.1.2.3 Mechanical Prope
12、rties After Simulated Elevated Temperature Exposure. Suppliers of aluminum hydroformed components to be used in elevated temperature vehicle locations such as the motor compartment, and near the exhaust system shall submit mechanical property data following simulated elevated temperature exposure. S
13、upplier shall submit yield strength, ultimate tensile strength and total elongation measurements on hydroformed component samples following 205 C (302 F) exposure for one (1) hour, and 150 C (401 F) exposure for one thousand (1000) hours. Upon request, aluminum hydroformed component supplier shall s
14、ubmit elevated temperature exposure samples to GM materials engineer. 3.1.3 Surface Requirements. 3.1.3.1 Surface Preparation. Aluminum tubing and hydroformed components shall be free of white (aluminum oxide) corrosion and pitting. Refer to Aluminum Association publication QCA-2, “Visual Quality Ch
15、aracteristics of Aluminum Extrusions” for photographs and definitions of pitting and water stain corrosion. It is preferable that tubes being prepared for shipment are washed, rinsed, and then coated with a GM approved corrosion preventative compound. If a washing process is used, it must not leave
16、insoluble residue that interferes with proper operation of bending and hydroforming equipment, welding, phosphating, or painting. Processing compounds (lubricants, cutting fluids, marking inks, etc.) and corrosion preventative compounds applied to hydroformed components that will be processed throug
17、h GM assembly plants shall be capable of being removed during paint system cleaning operation. Delivery of corrosion free hydroformed components may require packaging and/or use of corrosion preventative compounds. 3.1.3.2 Cleanliness. Tubing shall be clean and free of any contamination, including s
18、tringers, chips, solids, or excessive residues of any type on the outer diameter, inner diameter, and ends. 3.1.3.3 Surface Quality. The inside and outside surfaces of the tubing shall be free of surface discontinuities greater than 5% of wall thickness. Surface discontinuities include, but are not
19、limited to blisters, corrosion pits, blowholes, orange peel, stretcher jaw marks, and speed tears. Refer to Aluminum Association publication QCA-2, “Visual Quality Characteristics of Aluminum Extrusions” for photographs and definitions of discontinuities. Upon request, supplier shall provide boundar
20、y samples of worst case surface discontinuities to GM materials engineer for documentation of location and severity. Supplier shall also retain of duplicate worst case surface discontinuities boundary samples. 3.1.3.4 Pre-lube Application. If pre-lubricated tubing are to be supplied, the lubricant m
21、ust conform to GMW3059, and when applicable 9984309. 3.1.3.5 Surface Roughness. The surface roughness shall not exceed RA = 20 max = 70 Note that surface discontinuities described in 3.1.3.3 shall not be included in the surface roughness measurement. Surface roughness shall be measured in the longit
22、udinal direction according to SAE J911. 3.1.4 Product Integrity. 3.1.4.1 Longitudinal Weld Seam Integrity. If a porthole extrusion process is used to manufacture tubing, longitudinal weld seams shall be of sufficient strength such that structural integrity is not compromised. Weld seam integrity sha
23、ll be demonstrated by subjecting extruded tube samples to drift/flare testing. Refer to ISO 8493 for drift/flare testing general guidelines. Tube samples shall be subjected to constant axial load until fracture occurs. See Appendix C for drift/flare test procedure and pass/fail criteria. Supplier sh
24、all submit a schematic diagram showing location of longitudinal weld seams around the tube circumference. Refer to Figure B1 for an example of a longitudinal weld seam location diagram. 3.1.4.2 Transverse Weld Seams. Aluminum mechanical tubing supplied to this specification shall not contain transve
25、rse weld seams. Transverse weld seams shall be removed during extrusion process. 3.1.4.3 Internal Integrity. Aluminum mechanical tubing supplied to this specification shall be free of internal discontinuities that may compromise the structural integrity. Internal discontinuities include, but are not
26、 limited to laminations, unhealed billet cracks, porosity, and stringer inclusions. Refer to Aluminum Association publication QCA-2, “Visual Quality Characteristics of Aluminum Extrusions” for photographs and definitions of discontinuities. 3.1.4.4 Back End Condition. Aluminum mechanical tubing supp
27、lied to this specification shall be free of oxides and inclusions commonly known as “Back End Condition”. Suppliers shall process billets such that butt ends are sheared in such a way to avoid the presence of this condition in aluminum mechanical tubing. 3.1.5 Microstructure Requirements. The micros
28、tructure shall be homogeneous along the length and circumference of the aluminum mechanical tubing. Tubes supplied to this specification shall contain minimal large recrystallized grains at outer surfaces commonly known as periphery coarse grain, or coarse grained Copyright General Motors Company Pr
29、ovided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW16866 Copyright 2013 General Motors Company All Rights Reserved March 2013 Page 3 of 16 recrystallized outer band. Supplier
30、shall provide reference photomicrographs with grain size measurements to document periphery coarse grain or coarse grained recrystallized outer band grain size. 3.2 Processing Requirements. 3.2.1 Chemical Requirements. 3.2.1.1 Zinc Phosphate and/or Nano Ceramic Conversion Coating Analysis. For alumi
31、num hydroformed components that will be processed through GM assembly plant paint systems, supplier shall have zinc phosphate and/or nano ceramic conversion coating analysis performed on production representative samples. Zinc phosphate shall meet GMW3011 crystal size, coating thickness and coating
32、weight requirements. Nano ceramic conversion coatings shall meet GMW16170 coating thickness and coating weight requirements. Supplier shall have analysis performed by GMW3011 zinc phosphate supplier and/or GMW16170 nano ceramic conversion coating supplier, or a GM approved independent testing labora
33、tory. 3.2.1.2 Adhesive Compatibility. When applicable, aluminum hydroformed components supplied to this specification shall meet the adhesive compatibility requirements of GMW16549. Testing shall be performed on an aluminum hydroformed component sample which has been subjected to production represen
34、tative processing compounds (lubricants, cutting fluids, marking inks, etc.) and/or corrosion preventative compounds. Aluminum hydroformed component may require pre-treatment (i.e., conversion coating) processing per GMW16721 prior to adhesive bonding. 3.2.2 Physical Requirements. 3.2.2.1 End Finish
35、. Tubing ends must be burr-free and pinch-free. No sharp edges allowed at tube ends. Outside condition of as-received tubes is not to interfere with clamping or sealing ability. 3.2.2.2 Labeling and Traceability. Tubing blanks must have an ink stamp for “lot” identification. The ink used must surviv
36、e any subsequent thermal treatment, should be insoluble in water, and should be applied at three locations (lead end, middle, and tail end) along the length of the tube (Refer to Figure A2). 3.2.2.3 Dimensional Tolerances. Unless otherwise specified in electronic math data files, or on engineering d
37、rawings, Tubing dimensional tolerances shall conform to Table A3. 3.2.3 Additional Requirements. 3.2.3.1 Joining. When applicable, aluminum hydroformed components supplied to this specification shall be suitable for welding and mechanical clinching by standard GM methods. 3.2.3.2 GM Material Propert
38、y Database Sample. Upon request, hydroformed component supplier shall submit sample to GM materials engineer to generate data for the GM Material Property Database. Samples shall be at least 200 mm (8 in) in length. 3.3 Performance Requirements. Not applicable. 3.4. Requirements on other Stages duri
39、ng Life Cycle. Not applicable. 4 Manufacturing Process Aluminum mechanical tubing can be manufactured by seamless, or porthole die extrusion processes. Seamless extruded tubes, as defined in ASTM B241, is an extrusion which does not contain any longitudinal weld seams resulting from method of manufa
40、cture. If a porthole die extrusion process is used, as defined in ASTM B221M, longitudinal weld seams must be of sufficient quality to not fracture or split during hydroforming. 5 Rules and Regulations 5.1 Legal Regulations. All materials must satisfy applicable laws, rules, regulations and recommen
41、dations 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 components or materials released to a GM material specification shall be tested for conformity
42、 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 changes, e.g., properties, manufacturing process, location of manufacture, etc. If not otherwise ag
43、reed, all testing and documentation normally required for initial release must be completed. Copyright 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
44、 GMW16866 Copyright 2013 General Motors Company All Rights Reserved March 2013 Page 4 of 16 It is the responsibility of the supplier to inform the customer in a timely manner, without solicitation, and to include documentation of all modifications of materials and/or processes and to apply for a new
45、 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 can be agreed to between the responsible Engineering department and the supplier. 5.4 Material
46、Safety Data Sheets/Safety Data Sheets (MSDS/SDS). For new product submissions, or when a change in chemical composition of an existing product has occurred, a complete copy of the Material Safety Data Sheet/Safety Data Sheet must be submitted in compliance with the Globally Harmonized System of Clas
47、sification and Labeling of Chemicals (GHS) requirements or other country-specific MSDS/SDS requirements. In addition, product MSDS/SDS submissions must be in compliance with specific country General Motors TMC003 Material Safety Data Sheet/Safety Data Sheet guidance documents where available. 5.5 Al
48、l materials supplied to this standard must comply with the requirements of GMW3059, Restricted and Reportable Substances for Parts. 6 Approved Sources Materials supplied to this specification must be approved by General Motors. The appropriate GM Materials Engineering department(s) must confirm mate
49、rial as meeting the requirements of this specification. Any test data sheets of material submitted to General Motors for such confirmation (e.g., during Production Part Approval Process (PPAP) under this material specification must list all properties and must apply corresponding test methods of this material specification. Prototype, PPAP, GP-12/Launch, and Production data submission requirements are shown in Appendix B and Table B1. 7 Notes 7.1 Glossary. MATSPC: Global
