Flow Softening Behavior during Hot Deformation Processes of 7005 Aluminum Alloy at Medium Strain Rate

摘要

During the hot deformation of 7005 aluminum at medium strain rate of 50s~(-1), the flow stress curves exhibit continuous flow softening. After the correction for deformation heating, the flow softening still exists at high temperatures. EBSD observations indicate that the remaining softening is associated with grain boundary migration during dynamic recovery process. The flow softening of dynamic grain boundary migration (DGBM) and deformation heating both were removed from the flow stress curves. After ignoring those two flow softening mechanisms, the flow stress curves reach steady state values after its peak value at all deformation temperatures, which are similar with the shape of typical dynamic recovery flow stress curves. It is conclude that in addition to dynamic recovery the deformation heating and DGBM are dominated flow softening mechanisms for 7005 aluminum alloy during hot deformation.