超高强度热轧钢板冷冲压开裂原因及分析

Crack analysis of super high strength steel plate during cold stamping process

针对屈服强度700 MPa级超高强度热轧钢板冷冲压时出现开裂现象,对其剪切加工方式以及剪切材料端部进行了研究。结果表明,剪切端局部加工硬化以及大量残留的微裂纹扩展是700 MPa级热轧超高强钢板冲压产生开裂的主要原因。通过边缘局部回火或局部修磨去除裂纹源,可避免出现开裂或者降低开裂几率。

In accordance with crack of 700 MPa （yield strength） grade steel during the cold stamping process, the shear mode and the end of sheared steel were studied. The results show that local work hardening of the end of sheared steel and residual micro-crackle are main reasons that lead to crack with 700 MPa grade steel. The crack can be avoided or the rate of crack can be decreased through tempering with end of sheared steel and edge grinding to eliminate the crack source.