【摘要】 运用有限差分法,对超轻Mg-Li合金(LA141)板坯直冷连铸过程温度场进行数值模拟,根据实际过程的物理现象以及文献资料确定包括一冷区、二冷区在内的边界条件,并且考虑底模与铸坯之间随着铸坯的变形而引起的换热系数的变化。通过计算铸坯内温度场的分布,固-液界面的形状和位置,分析各种铸造参数,包括浇注温度、冷却水量、铸造速度等对连铸过程的影响。另外也比较了在同等铸造条件下LA141铸坯和AZ31铸坯铸造过程中凝固前沿的形状。更多还原

【Abstract】 A mathematical model of the direct chill (DC) casting process for superlight Mg-Li alloy (LA141) slab has been developed using the finite differential method (FDM). Thermal boundary conditions including primary and secondary cooling conditions, have been selected based on knowledges of the physical process and the literatures. The variations of heat transfer coefficient between slab and dummy block interface resulting from the deformation of the slab have been considered. By calculating the temperature distribution, solid-liquid interface shape and position, the influence of casting parameters on DC casting process, such as the pour temperature, cooling water flow rate and casting speed have been analyzed. Moreover the profiles of the solidification fronts during the casting processes for the alloys of LA141 and AZ31 are compared.更多还原