Warm forming behavior of high strength aluminum alloy AA7075
(1. College of Mechanical and Electrical Engineering,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
2. Department of Manufacture, Ford Motor Company, Dearborn, MI, 48124, USA)
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China
2. Department of Manufacture, Ford Motor Company, Dearborn, MI, 48124, USA)
Abstract: The formability of aluminum alloy AA7075 at elevated temperature was investigated through experiment. Stress—strain relationship at different temperatures and forming speeds were investigated through tensile testing. Deep drawing and stretch formability were also tested through limiting drawing ratio (LDR) and limiting dome height (LDH) tests. Finally, post forming mechanical property testing was conducted to investigate the effects of exposure to warm forming temperatures on the mechanical properties. Results show that deep drawing and stretch formability of AA7075 can be significantly improved when the blank is heated to 140−220 °C. At temperature over 260 °C, formability and post forming mechanical properties begin to decrease due to the effect of the heating and forming processes on the material’s temper.
Key words: aluminum alloy 7075; warm forming; limiting drawing ratio (LDR); limiting dome height (LDH)