Abstract:Aiming at the surface indentation defects of thick dual-phase wheel steel, the relationship between indentation defect and thickness of iron oxide scale was analyzed. It is concluded that the quite thick oxide scale is the root cause of surface indentation defect for thick dual-phase wheel steel. Combined with the analysis result of the formation rule of iron oxide scale and the production process characteristics of thick dual-phase wheel steel, the technical idea and control target for reducing the thickness of iron oxide scale were determined by increasing the finish rolling speed. On this basis, a post rolling cooling device configuration technology of preposed ultra-fast cooling + conventional cooling + post ultra-fast cooling was proposed, and a control strategy for initial setting of finish rolling speed with speed priority was developed. They were applied in the 2 250 mm hot rolling production line of Shougang Jingtang Company, which effectively solved the surface indentation problem of dual-phase wheel steel. The defective rate caused by indentation defect was reduced from 30% to 3%. It plays an important role in promoting stable batch production of dual-phase wheel steel and improving product quality.
艾矫健, 王文广, 李兴波, 李建伟. 厚规格双相车轮钢表面压痕缺陷分析及控制[J]. 中国冶金, 2023, 33(8): 126-130.
AI Jiaojian, WANG Wenguang, LI Xingbo, LI Jianwei. Cause analysis and control measures of surface indentation defect of thick dual-phase wheel steel[J]. China Metallurgy, 2023, 33(8): 126-130.