T8钢冷剪下料时端部断裂及坏头原因分析  

Causes Analysis of End Cracks and Damaged Top of Steel T8

作　　者：张燕东 姜太琼 何小林 贺文成 侯平杰 李明林 

机构地区：[1]西宁特殊钢集团公司,青海西宁810005

出　　处：《物理测试》2014年第2期40-43,共4页Physics Examination and Testing

摘　　要：T8钢用冷剪下料时,A厂钢材出现端部开裂及坏头的比例较大,B厂材料出现端部开裂及坏头的比例较小。分别选取A厂与B厂相同规格的T8钢,对比分析钢的化学成分、非金属夹杂物、布氏硬度、金相组织。分析结果表明:1)造成材料剪切端面裂纹的原因是钢材硬度偏高;2)A厂T8钢材质硬度偏高的主要原因是钢中的碳含量偏高,加上钢材终轧温度低,钢材轧后在冷床上停留时间长,钢材堆冷时温度偏低,与钢材的内部质量无关。When cold shearing was applied on steel T8, there were larger proportion end cracks and damaged top on the steel T8 produced by Plant A. While on the steel of Plant B, the percentage is small. Therefore, the same sized steel T8 were chosen from both Plants and investigation was conducted on their chemical compositions, non-metallic inclusions, brinell hardness and metallographic structure. The results showed that the reason of end cracks by cold cutting is due to its high hardness. High carbon content in the steel resulted in high hardness of steel T8 manufac- tured by Plant A. Besides, the lower final rolling temperature, longer staying over on cooling beds after rolling and lower pile-cooling temperature all contributed to make the problem worse. However, the internal quality of the steel has no effect on it.

关 键 词：T8钢 端部裂纹 坏头 硬度 应力开裂 

分 类 号：TG142.45[一般工业技术—材料科学与工程]