履带销轴线切割开裂机理分析

Analysis for Cracking of Track Pin in the Process of Wire-cutting

某公司生产的履带销轴在线切割加工过程中发生开裂,通过化学成分分析、金相组织检验、硬度测试、扫描电镜分析等方法,分析了产品的开裂原因,同时提出了相应的改进措施。结果表明:销轴表面淬火后横截面的硬度分布不均匀,形成较大残余应力,线切割过程中应力再平衡导致开裂。在生产实践中,通过粗车后调质提高芯部硬度,有效防止开裂。

Crack is occurred in the wire-cutting process for track pin produced by a company.The fracture reasons of the track pin were analyzed by means of chemical composition,metallographic examination,hardness test,SEM analysis,etc.At the same time,the corresponding improvement measures were put forward.The results show that the hardness distribution of the cross section of the pin shaft after quenching is not uniform,resulting in a large residual stress,and the stress rebalancing in the process of wire cutting leads to cracking.In production practice,the hardness of the pin shaft core can be improved by quenching and tempering after rough turning,which can effectively prevent cracking.