凝固组织数值模拟中晶粒接触因素的修正系数

A New Correction Coefficient for Better Prediction of Solidified Structure

通过数值计算与实验相结合的方法 ,对凝固组织数值模拟中晶粒接触因素修正系数的已有形式进行了分析、比较。在此基础上 ,提出了当固相体积分数 (fs)大于π/6后采用 [1 - (fs -π/6 ) ]4 作为反映晶粒接触因素的修正系数是一种更合理的形式。经实验验证 。

It is well known that structure determines material properties. To reflect the fact that crystal growth during the later stage of solidification is different from that during its initial stage, past researchers introduced two typical impingement correction coefficients to improve the prediction of solidified structure. But their improvement appears to be still not quite adequate. Based on our numerical simulation and experiments, we propose using the formula [1-( f s -π/6)] 4 as a new correction coefficient, where f s , the solid volume fraction, is larger than π/6. The test results, shown in Fig.1 together with cooling curves based on two existing impingement correction coefficients and our new impingement correction coefficient respectively, show that our new impingement correction coefficient is better than existing impingement correction coefficients in agreement with test data. Thus our new correction coefficient appears promising to give better prediction of solidified structure.