430不锈钢热轧板坯边部侧翻缺陷形成的数值模拟

Numerical Simulation of Edge Side Rollover Defect Formation of 430 Stainless Steel Hot Rolled Slab

在不同温度(1173.15~1473.15 K)和应变速率(0.01~10 s^(-1))下对430不锈钢进行热压缩变形试验,基于流变数据建立修正的Zerilli-Armstrong方程,并评估该方程的预测能力;将该本构方程参数导入Deform-3D软件,对试验钢五道次可逆热轧变形进行有限元模拟,分析边部缺陷的形成过程,并与实际轧制缺陷进行了对比。结果表明:修正的Zerilli-Armstrong本构方程能够很好地描述试验钢的高温流变行为,流变应力预测值和试验值之间的相关系数为0.9939,平均相对误差为5.9%;模拟得到在轧制过程中轧辊与板坯之间的摩擦力使得板坯表面和内部存在横向位移差,导致板坯侧面节点上翻到表面形成边部侧翻缺陷,缺陷的位置和形貌与工业试制结果相吻合。

The thermal compression deformation tests of 430 stainless steel were carried out at different temperatures(1173.15-1473.15 K)and strain rates(0.01-10 s^(-1)).Based on the rheological data,the modified Zerilli-Armstrong equation was established and its predictive ability was evaluated.The parameters of the constitutive equation were introduced into Deform-3D software to simulate the deformation of test steel in five-pass reversible hot rolling.The forming of edge defects was analyzed and the defects were compared with the actual rolling defects.The results show that the modified Zerilli-Armstrong constitutive equation could well describe the rheological behavior of the test steel at high temperature.The correlation coefficient between the predicted and the test flow stresses was 0.9939,and the average relative error was 5.9%.The friction force between the roll and the slab caused the lateral displacement difference between the surface and the inside of the slab during rolling,which led to side joint turning up to the surface and the formation of edge side rollover defect.The location and morphology of the defects were consistent with the results of industrial trial production.