GMW18378, 1st Edition, June 2021 - Heat-Treatable 7000 Series Aluminum Sheet

Note: Nothing in this standard supercedes applicable laws and regulations. 

Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 

Purpose/Material Description. 

This specification covers the requirements for heat-treatable 7000 series aluminum used in the manufacture of structural parts to manage very high tensile loads without significant deformation as required in safety and occupant protection. This material is heat treated, formed and simultaneously quenched in a water-cooled die in a process referred to as hot stamping. 

The material designation is defined by the GMW material specification number. The aluminum grades will correspond to the chemical and mechanical requirements as shown in Appendix A, Table A1 through Table A2. Only the surface quality designation of U, representing an unexposed application, shall be used unless otherwise approved by Materials Engineering. 

Hot Stamped Die Quenched Aluminum. 

Parts shall be made by solutionizing a pre-cut blank, hot stamping the heated blank and rapid cooling (quenching) the stamped part in the die. 

Material Callouts. 

The list of material and coating designations shown in Table 1 are the only approved material callouts that can be released unless GM Materials Engineering and the appropriate Global Subsystem Leadership Team approves. 

Symbols. 

Not applicable. 

Applicability. 

Typical applications are sheet metal stampings requiring tensile strength minima ranging from 475 MPa to 550 MPa. Typical applications include door impact beams, bumper impact beams and structural reinforcements for side impact, roof strength, and impact energy management.