电磁铸造大板坯凝固过程中热裂纹萌生机理分析

INITIATION MECHANISM OF THERMAL CRACK DURING SOLIDIFICATION OF EMC SLAB

依据电磁铸造（ＥＭＣ）大板坯凝固进程的数值模拟结果，建立了预测热裂纹萌生部位及应力的解析表达式对板坯产生的裂纹及其材质的组织结构的评价表明：热裂纹的萌生与材料的力学性能及组织结构没有必然联系；控制凝固过程中板坯表面温度是减少热裂纹萌生的有效方法。所得结果与裂纹实际情况吻合。

Based on the numerical simulation of solidification of EMC(electromagnetic casting) slab,a formula estimating the thermal stress and the location where the thermal crack initiates are proposed.The result indicates that the temperature on the surface of slab is a key factor to predict thermal stress and crack.By means of some technology,if the cooling rate on the surface of EMC slab is controlled so that the temperature in the solidified shell remains higher,the thermal crack may be avoided.