摘要
42CrMo钢汽车用连轴杆淬回火后出现断裂,使用火花放电直读光谱仪进行化学成分分析,参照标准对样品断口附近横向试样进行了低倍组织缺陷对比,使用光学显微镜和扫描电镜对样品的显微组织、断口微观形貌、夹杂物进行检测,分析表明,样品有中心缩孔缺陷存在,判定连铸时材料已形成中心缩孔缺陷,后续轧制时不能愈合,淬火过程中样品的应力分布促进残余缩孔裂缝的快速扩展,同时中心缩孔在材料后续加热过程中,在缺陷周边可产生铁氧化物,且铁的氧化物塑性很差,难以协调变形,共同作用下发生断裂。
42CrMo steel coupling rod for automobile broke after quenching and tempering.Chemical composition was analyzed by spark discharge direct reading spectrometer.Low magnification structure defects of transverse sample near fracture were compared with standard.Microstructure,fracture morphology and inclusions of sample were detected by optical microscope and scanning electron microscope.The analysis shows that there are central shrinkage defects in sample.The central shrinkage defects have been formed during continuous casting and can not be healed during subsequent rolling.The stress distribution of sample during quenching promotes rapid expansion of residual shrinkage cracks.During subsequent heating process,iron oxide can be produced around the central shrinkage cavity.The plasticity of iron oxide is very poor,it is difficult to coordinate deformation,and fracture occurs under joint action.
作者
王鹏举
郭磊
陈占杰
尹亚豪
Wang Pengju;Guo Lei;Chen Zhanjie;Yin Yahao(Sinosteel Zhengzhou Research Institute of Steel Wire Products Co.,Ltd.,Zhengzhou 450001,China;Anyang Iron&Steel Group Co.,Ltd.,Anyang 455000,China)
出处
《金属制品》
CAS
2021年第5期57-60,共4页
Metal Products
