Effects of different hot rolling processes on microstructure of hot-rolling and heat-treatment 7055 aluminum alloy have been investigated by hot rolling

heat-treatment and optical microscope observation

in which the hot rolling processes included general process and the process of severe reduction for per pass.The results show that

after severe reduction for per pass

uniform deformed microstructure in the center part can be observed in 7055 aluminum alloy plate

and the coarse second phase is sufficiently broken up.The second phase is fully dissolved into the center part of the plate rolled by the process of large reduction for per pass after solid-solution at 470 ℃ for 90 min.Compared with those by general rolling process

the recrystallization grain volume fraction is decreased by 15% in the plate rolled by the process of large reduction for per pass after aged at 120 ℃ for 24 hours.