Abstract: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.
雷凯, 万佳峰, 孙卫华, 胡华东. 热连轧低合金钢边部横裂形成原因分析[J]. 中国冶金, 2021, 31(7): 92-99.
LEI Kai, WAN Jia-feng, SUN Wei-hua, HU Hua-dong. Cause analysis of edge transverse crack in hot continuous rolling low alloy steel[J]. China Metallurgy, 2021, 31(7): 92-99.