Influence of pre-treatment process on recrystallization behavior of twin roll cast 3003 Al alloys

Three kinds of pre-treatment process were carried out in a twin roll cast 3003 Al alloy sheet. The evolution of grain structure and recrystallization texture was investigated in the pre-treated sheet after cold-rolling and annealing at 380-500 degrees C. The results show that the optimized pre-treatment is determined to be 610 degrees C for 12h followed by 460 degrees C for 12h. Second phase particle coarsening occurs at high temperature stage and the Mn concentration in solid solution decreases at low temperature stage, both of them can promote the recrystallization nucleation rate during the subsequent annealing. During annealing at 500 degrees C, particle stimulated nucleation occurs in the vicinity of the coarse second phase, leading to a reduced texture intensity; in addition, precipitation is hardly found to occur during annealing and hence the inhibition of recrystallization nucleation is negligible, and finally the recrystallization structure with fine grains together with weakened texture is obtained.