厚规格车轮钢表面麻坑缺陷成因及控制策略

Cause analysis and control measures on pockmarks formed on the surface of thick automobile wheel steel strip

分析了厚规格车轮钢表面麻坑缺陷的微观形貌及成因,针对缺陷成因提出了相应的热轧生产控制策略。研究表明:厚规格车轮钢轧后氧化铁皮厚于常规钢种,用户开平过程中带钢表面氧化铁皮发生破碎后从带钢基体脱落,随开平过程被矫直辊压入带钢表面进而形成麻坑缺陷;采用"降温增水提速"的工艺措施,降低板坯出炉温度、精轧入口温度,增加精轧机架间冷却水量,提高精轧轧制速度,可以有效控制带钢表面氧化铁皮厚度,显著降低麻坑缺陷的发生率。

The micro morphology and cause of pit defect on the surface of heavy gauge wheel steel strip were analyzed,and the corresponding hot rolling production control strategies were proposed.The result showed that the iron oxide thickness of the thick gauge wheel steel after rolling were higher than conventional steel,the strip surface oxidized iron were broken from the strip matrix and pressed into the surface during decoiling and straightening.The strip surface oxidation thickness could be effectively controlled and the pit defect could be significantly reduced by corresponding measures,such as decreasing the slab tapping temperature and finishing rolling start temperature,increasing finishing rolling inter-stand cooling water amount,increasing finishing rolling speed.