GMW GMW18377 PDF

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 document describes the minimum process and internal testing requirements for producers of hot stamped parts. Aluminum Hot Stamping, or Hot Stamped Aluminum (HSA), utilizes a heat treatable aluminum such as 7075 that is heated to homogenize (solution treat) microstructure, followed by stamping in a water cooled die to produce the proper part shape and to simultaneously quench the aluminum to create a W-temper. This is followed by natural or artificial aging of formed parts. Parts may also be specified to contain soft zones, which are lower strength than the surrounding metal and may not be the fully strengthened structure. Parts may also be produced in an “intermediate” condition in order to accommodate subsequent processing such as a paint bake, which will affect properties in order to obtain specified final properties in the finished vehicle.

Symbols.

W:

Solution Treated Aluminum

T54:

Solution Treated following the shaping process and artificially underaged to a stable condition.

T6:

Solution Treated and artificially aged to maximum strength condition.

T61:

Solution Treated and artificially aged. No surface passivation, curing, or paint cure process applied.

T64:

Solution Treated, artificially aged and subsequently processed to the stable in-service condition, i.e., finished.

Applicability.

Typical parts covered by this specification are those that require extremely high strength and are generally critical to passenger safety. These parts are found throughout the body structure and closures, with typical applications including but not limited to door beams, center pillar reinforcements, floor reinforcements, and upper body roof rails.