中文摘要：

用多尺度模拟方法研究了近液相线半连续铸造中的ZL201合金的液/固相变。建立了描述连续铸造过程的温度场模型及相变模型,通过固相率变化将宏观和介观尺度上的模拟耦合起来。利用外推边界条件对ZL201合金在近液相线半连续铸造过程的稳态温度场进行了计算;根据连续铸造特点,提出了用液/固相变区域中元胞的平均过冷度作为形核计算的基本参数。对ZL201合金在铸造速度为1.5~10.0mm/s时的近液相线浇注的凝固组织进行了模拟。计算表明,铸造速度对半固态合金组织的形成有较大影响,当铸造速度在2.0~2.5mm/s时,可获得晶粒大小和分布良好的合金组织。

英文摘要：

The solid/liquid phase transformation of ZL201 aluminium alloy in near liquidus semi-continuous casting was simulated using multiscale simulation technique. The models of temperature fields and phase transformation were established with respect to the continuous casting process. The solid fraction was used to couple the model between on macro-scale and on mesoscale. The steady state temperature fields of ZL201 alloys were calculated using the extrapolated non-physical boundary proposed in this paper. The av...