糊状区变形及浓度再分布的模拟实验

用丁二腈－丙酮合金实验研究试样变形开始时间、初始厚度及变形量对枝晶变形及溶质再分布的影响。结果表明，枝晶变形满足幂次大于1的能量函数关系；枝晶变形能力主要与变形时糊状区固相分数有关；从糊状区挤出的液相相对浓度与固相分数、变形比率成线性关系。实验结果对建立糊状区变形与宏观偏析数学模型及优化连铸液芯压下工艺有意义。

EXPERIMENTAL STUDY ON THE MUSH DEFORMATION AND SOLUTE REDISTRIBUTION

The effects of deformation start time, initial thickness and deformation amount on both the deformation of dendrites and solute redistribution in mush of succinonitrile-acetone alloys have been experimentally studied. The results indicate that the deformation of dendrites satisfies a power function with the power larger than 1, the deformation ability of dendrites is mainly dependent on the solid fraction of mush, and the normalized concentration of liquid expelled from the mushy zone has a linear relationship with the solid fraction and the deformation rate of mush. These experimental results are helpful to build the mathematical model of mush deformation and macrosegregation, as well as to optimize the liquid core reduction technology in continuous casting process.