中文摘要：

建立了偏晶合金液-液相变过程中的两相流动模型,发展了偏晶合金凝固理论模型;以Al-Pb合金为例,模拟研究了偏晶合金凝固时的组织演变进程,考察了流动对凝固组织形成的影响.结果表明,对流影响液液相变的形核特性,提高凝固界面前沿最高弥散相液滴数量密度、最大液滴半径和最高弥散相体积分数,促进宏观偏析组织的形成.

英文摘要：

A two-phase convective flow model describing the microstructure evolution during the liquid-liquid phase transformation in monotectic alloy was developed by taking into account of the convective effect and used in analyzing Al-Pb alloy. The results indicate that the convection changes the nucleation behavior of the minority phase droplets, enhances the maximums of the number density, the radius and the volume fraction of the droplets in front of the solidification interface, and promotes the formation of the solidification microstructure with a serious macro segregation.