预处理工艺对双辊铸轧3003铝合金再结晶行为的影响

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

对双辊铸轧3003铝合金板材进行了3种预处理退火,研究不同预处理工艺下的冷轧板材在380～500℃退火时晶粒组织和再结晶织构的变化规律。结果表明:最优化预处理工艺为610℃/12h+460℃/12h,高温阶段第二相尺寸发生粗化,低温阶段基体中Mn的过饱和固溶度显著降低,两者均有利于提高后续退火时的再结晶形核率。500℃退火时,在粗大第二相的附近产生了粒子诱发形核机制,降低了再结晶织构强度;并且退火时几乎不存在析出,析出相对再结晶形核的抑制作用甚微,从而得到了晶粒细小、织构弱的再结晶组织。

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℃.The results show that the optimized pre-treatment is determined to be 610℃for 12h followed by 460℃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℃,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 recrysta-llization structure with fine grains together with weakened texture is obtained.