35CrMo钢螺栓断裂原因分析  

Analysis on Cause for Breaking of 35CrMo Steel Bolts

作　　者：韩克甲 李锦锦 聂小可 刘丽 HAN Kejia;LI Jinjin;NIE Xiaoke;LIU Li(National Pump product Quality Inspection and testing Center,Zibo 255063,Shandong China;Zibo Product Quality Inspection Research Institute,Zibo 255063,Shandong China)

机构地区：[1]国家泵类产品质量检验检测中心,山东淄博255063 [2]淄博市产品质量检验研究院,山东淄博255063

出　　处：《热处理》2023年第4期53-55,共3页Heat Treatment

基　　金：国家市场监督管理总局科技计划项目(2021MK060)。

摘　　要：一批35CrMo钢螺栓中有一部分使用了2个月后断裂。为揭示其断裂的原因,对断裂的螺栓进行了宏观检查、化学成分分析、抗拉强度和硬度检测、金相检验及断口分析。结果表明:螺栓有极不均匀的脱碳层,且抗拉强度低于要求值,导致使用中螺栓因螺纹根部形成细微的应力裂纹并逐步扩展而断裂。Some of a batch of 35CrMo steel bolts broke after two months of service.In order to reveal the cause of their fracturing,macro⁃check,chemical composition analysis,tensile strength and hardness measurements,metallographic examination,and fracture testing were performed on the broken bolts.The results showed that the broken bolts exhibited much uneven decarburized layer and tensile strength that was less than the required value,thus resulting in their breaking as a result of formation and gradual expansion of a fine stress crack at the thread root in service.

关 键 词：螺栓 脱碳 应力裂纹 

分 类 号：TG115[金属学及工艺—物理冶金]