22SiMn2TiB铲斗主刀板开裂原因分析

Cause analysis of cracking on main cutter board of 22SiMn2TiB bucket

通过化学成分分析、硬度分析、光学显微镜非金属夹杂分析及组织分析、扫描电镜断口分析及能谱分析等手段,对某钢厂厚度为32 mm的22SiMn2TiB钢板加工成铲斗主刀板的过程中少量工件垂直于火切边出现开裂甚至断裂的现象进行分析。结果表明:板材心部存在Si、Mn元素成分偏析使得板材心部成为整个工件应力最为集中的区域,在火切过程中心部区域先开裂,工件热处理时经高温氧化,在校直时裂纹进一步扩展是工件形成开裂的最主要因素。

22SiMn2TiB steel plate with a thickness of 32 mm was processed into the main blade of the bucket in a steel plant.In this process,few workpieces had cracking or even fracture perpendicular to the flame cutting edge.In order to analyze the causes of cracking,the samples were analyzed by means of chemical analysis,scanning electron microscope analysis and metallographic examination.It was found that the segregation in the center of steel plate was the main reason to cause workpiece cracking.