中厚板表面片状开裂原因分析及控制

Cause analysis and control of surface sheet crack in medium and heavy plate

针对中厚板表面片状开裂缺陷,采用光学显微镜及扫描电镜等设备对缺陷进行分析验证。结果表明,开裂的原因是扇形段辊子上铜制的轴承保持架破损压入铸坯,在轧制过程中造成开裂并扩散;而轴承破损主要是由于高温环境下设备冷却及润滑不良,通过更改轴承材质、改善轴承润滑油路、冷却水路等措施,片状开裂缺陷得到有效控制。

In order to study the surface sheet crack in medium and heavy plate,the methods such as the scanning electron microscope and optical metallograph were used to analysis the defect.The results showed that disabled bearing cage made of Cu was pressed into slab,and then the crack formed and enlarged during rolling.The failure of bearings was caused by the bad cooling and lubrication conditions under high temperature.By changing the material of bearing cage,improving the lubrication and cooling conditions,the defect of surface sheet cracking was solved effectively.