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Title: Review of Retrogression Forming and Reaging for AA7075-T6 Sheet
Retrogression forming and reaging (RFRA) is a new warm-forming process designed to produce automotive structural components from high-strength aluminum alloys. A scientific approach is described to determine appropriate RFRA conditions for AA7075-T6 and is applied to laboratory-scale forming experiments. The concept of reduced time is used with the activation energy of retrogression measured for AA7075-T6 to predict appropriate times and temperatures for retrogression forming. Conditions recommended for AA7075-T6 are retrogression at 200 °C for 3 to 12 min while forming at strain rates of up to 10^{–1} s^{−1}. The recommended reaging heat treatment to fully restore strength to the T6 condition after retrogression forming is 120 °C for 24 h. These RFRA conditions were successfully applied in laboratory-scale experiments to form AA7075-T6 Alclad sheet and produce a final strength equivalent to the T6 condition. Data from tensile tests provide flow stresses and tensile ductilities across the range of conditions appropriate for RFRA.  more » « less
Award ID(s):
1634495
PAR ID:
10298900
Author(s) / Creator(s):
; ; ;
Editor(s):
Perander, L.
Date Published:
Journal Name:
Light Metals 2021, The Minerals, Metals and Materials Series
Page Range / eLocation ID:
206-211
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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