轧制边线形成过程的有限元分析

Finite element analysis of edge seam defect during rolling process

利用有限元软件对空冷后具有一定温度梯度的板坯的轧制过程进行数值模拟计算,研究分析两种不同高温力学特性的钢种在轧制时边角部金属的位移、应变及应力情况,分析边部线状缺陷起源的褶皱的形成过程并通过轧制试验予以验证。分析结果表明,边线形成与变形温度范围内变形抗力的不连续变化具有明显相关性,变形抗力随温度连续变化的钢种轧制过程角部金属不会形成褶皱;变形抗力随变形温度不连续变化的钢种,当板坯角部金属进入两相区时,由于轧制过程两相区变形抗力出现谷值,易出现褶皱并最终演变为边部线状缺陷。

The rolling process of air-cooled slab with a certain temperature gradient is numerically simulated by using finite element method.The displacement,strain and stress of edge and vertex metals during rolling of two steel grades with different high temperature mechanical properties were studied and analyzed.The formation process of wrinkle as the origin of edge seam defect is analyzed and verified by rolling test.The analysis results show that the formation of edge seam defect is obviously related to the discontinuous change of deformation resistance in the range of deformation temperature.The vertex metal will not wrinkle during the rolling process of steel grades whose deformation resistance varies continuously with temperature;For steel grades whose deformation resistance varies discontinuously with the deformation temperature,when the vertex metal of slab enters the two-phase region,wrinkle will occur and eventually develop into edge seam defects due to the valley of deformation resistance in the two-phase region during rolling.