화학공학소재연구정보센터
Materials Science Forum, Vol.426-4, 291-296, 2003
The interaction between precipitation and recrystallization during annealing of cold rolled AA6111
The present work examines the effect of different initial precipitation states on the recrystallization behaviour of a cold rolled aluminum alloy, AA6111, which is used for automotive sheet applications. The recrystallization kinetics are followed by softening measurements and optical microscopy. The softening behaviour is rationalized by considering the evolution of precipitates during annealing. It is found that a substantial amount of softening can be attained without a significant degree of recrystallization irrespective of the initial precipitation conditions. The loss of yield stress is mainly caused by recovery and coarsening of precipitates. Recrystallization is severely retarded due to the pinning effect of precipitates on grain boundaries. The work hardening behaviour is elucidated by using a generalized flow stress addition law.