汽车用冷轧高强钢DP980边裂分析与控制

EDGE CRACK ANALYSIS AND CONTROL OF COLD ROLLED HIGH STRENGTH STEEL DP980 FOR AUTOMOBILE

介绍了高强钢DP980冷轧边裂缺陷的特征,并分析了边裂产生的原因及机理。结果表明:DP980钢在层流冷却尤其是卷取后,边部冷速过快造成晶粒细小,大量马氏体及马奥岛等硬相组织形成,从而导致其在冷轧过程中因边部塑性低而产生边裂。通过增设边部加热器、加装保温罩,优化冷轧轧机张力与压下率分配,有效地降低了边裂发生率。

The characteristics of edge crack defect of high strength steel DP980 cold rolled steel are introduced, and the causes and mechanism of edge crack are analyzed. The results show that, the excessive edge cooling rate of DP980 steel after laminar cooling, especially coiling, resulas in the fine grains and a large number of hard phase structure such as martensite and MA island, which leads to edge crack due to low edge plasticity during cold rolling process. By adding edge heater and heat insulation cover, optimizing the tension and reduction ratio distribution of cold rolling mill, the occurrence rate of edge crack is effectively reduced.