Complicated physical processes including nucleation,diffusional growth,Marangoni migration,gravity migration and collision coagulation of rich Bi droplets under different solidification time and temperature during the solidification of Al-Bi alloys though very fast liquid quenching cooling experiment in normal gravity condition were analyzed.The average and max diameter of drops,as well as the distribution regularity of the max drops with time variation were studied.The formation of macro segregation of monotectic alloys and its influencing factors were also revealed.Theoretical reference and experimental foundation were provided to prepare uniformity monotectic alloys.%在常规重力场条件下,通过极快速液淬冷却的实验方法,分析了Al-Bi过偏晶合金在难混溶区凝固过程中,不同凝固时刻和温度下富Bi相液滴的形核、扩散长大、Marangoni迁移、重力沉降和碰撞凝并等复杂的物理过程,考察了富Bi相液滴平均直径及最大直径等随时间变化的分布规律,揭示了偏晶合金宏观偏析的形成过程与影响因素的作用程度,为制备匀质偏晶合金提供理论参考和实验依据.
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