热连轧低合金钢边部横裂形成原因分析

通过采集现场过程数据,从温度、成分、相变、晶粒形貌、轧制变形应力等方面对低合金钢Q355B宽规格钢板在热连轧过程中产生边部横向裂纹缺陷的原因进行机理分析.结果 表明,宽规格低合金钢边部横向裂纹产生原因与板坯宽度方向温度均匀性相关,边部局部温度过低导致两相区和非再结晶区域轧制,边裂区晶粒度尺寸和形貌与正常区有明显差异,从...

Cause analysis of edge transverse crack in hot continuous rolling low alloy steel

By collecting the field process data, the causes of edge transverse crack defects of low alloy steel Q355B wide gauge plate during hot continuous rolling were analyzed in terms of temperature, composition, phase transformation, grain morphology and rolling deformation stress. The results show that the cause of the transverse crack at the edge of wide specification low alloy steel is related to the temperature uniformity in the width direction of slab. The low temperature at the edge causes the rolling in the two-phase area and non-recrystallization area. The grain size and morphology in the edge crack area are obviously different from those in the normal area, which results in the inconsistent elongation of the surface layer and the subsurface layer during the rolling process. The tensile deformation resistance of the local metal exceeds the tensile strength at high temperature. Leading to the formation of transverse crack defects on the surface.