Abstract:The isothermal hot compression tests of 7085 aluminum alloy were carried out at a constant strain rate and temperatures from 350 to 450 ℃ to simulate the isothermal forging process. The effects of hot deformation temperature on microstructure, mechanical properties , exfoliation corrosion property and stress corrosion property of 7085 alloy were investigated by optical microscope, scanning electron microscope, mechanical property testing, exfoliation corrosion and stress corrosion cracking testing. The results show that the recrystallization during the isothermal hot compression process and subsequent slow cooling is not activated when the alloy is deformed at 350 and 400 ℃, respectively.  However, the recrystallization happens obviously when the alloy is deformed at 420 and 450 ℃, respectively. After solution treatment and aging treatment, the recrystallization and mean grain size of the alloy increase with raising hot deformation temperature. With the increase of deformation temperature, the strength of aged 7085 alloy at room temperature decreases, but the elongation decreases a little. The fracture models of all aged alloys deformed at different temperatures are ductile fracture. The exfoliation corrosion resistance and anti-stress corrosion cracking properties of peak-aged 7085 alloys decrease with the increase of deformation temperature.

Key words: 7085 alloy; hot deformation temperature; microstructure; mechanical properties; exfoliation corrosion; stress corrosion