热轧板条纹缺陷分析

Analysis of hot-rolled plate stripe shape defect

热轧板表面条纹缺陷为热轧板常见缺陷,且较难治理。为了弄清热轧板表面的条纹缺陷产生原因,利用金相显微镜和扫描电镜等设备进行了分析。结果表明:缺陷区存在再结晶不完全的大晶粒和脱碳现象,以及内氧化质点。说明铸坯原生缺陷有高温加热、轧制的痕迹。大晶粒的形成可能是由于缺陷处于临界应变状态或细化晶粒的元素被氧化掉,或两种因素共同作用的结果。裂纹与热轧板表面夹角很小,裂纹毗邻金属存在脱碳及内氧化斑点等,缺陷性质也可能是热轧过程中形成的折叠。

The striped surface defect is the common defects for hot-rolled plates, and it is difficult to control. The causes of hot-rolled plate stripe shape surface defects was analyzed by optical microscopy,scanning electron microscopy and other equipments. The results show that there was incomplete recrystallization of large grain size and decarburization in the defective area,as well as the oxide particles. There was high temperature heating and rolling traces in the primary defect of billet. Large grain formation may be due to a defect in the state of critical strain or oxidized elements of grain refinement, or interaction between the two factors. There are many small angle between the cracks and the surface of hot-rolled plates. At the same time, there are many decarbonization and metal oxide spots and other defects adjacent to the cracks,the defects may be fold formed during hot-rolling.