20Cr2Ni4钢齿轮渗碳淬火及装配后开裂原因分析  

Crack analysis of case-hardened 20Cr2Ni4 steel gear after assembly

作　　者：许鸿翔 王红伟 张衡 汪军 赵少甫 Xu Hongxiang;Wang Hongwei;Zhang Heng;Wang Jun;Zhao Shaofu(Zhengzhou Research Institute of Mechanical Engineering Co.,Ltd.,Zhengzhou Henan 450001,China)

机构地区：[1]郑州机械研究所有限公司,河南郑州450001

出　　处：《金属热处理》2021年第8期250-253,共4页Heat Treatment of Metals

摘　　要：采用光学显微镜、显微硬度计和光谱分析仪等测试方法,对20Cr2Ni4钢齿轮渗碳淬火及装配后开裂的原因进行分析。结果表明,该渗碳淬火齿轮齿顶硬度和硬化层深度均满足要求,显微组织良好。轮辐减重孔处为裂纹源,减重孔内壁明显的粗刀痕形成的应力集中导致齿轮与轴系装配后裂纹逐步扩展到齿轮内孔,进而导致开裂失效,并据此提出了改进措施。Failure reason of the case-hardened 20Cr2Ni4 steel gear after assembly was analyzed by means of OM,micro-hardness tester and spectrometer.The results show that the tooth top hardness and hardened case depth of the carburized and hardened gear all meet the requirements and the microstructure is good.The cracks source is at the weight-reducing hole of spoke,and the rough tool marks obviously formed in the inner wall of weight-reducing hole can lead to the stress concentration,resulting in the cracks of gear and axle after assembly expanding to the inner hole of gear gradually.And then the fracture failure is occurred,finally some improvement measures are put forward.

关 键 词：齿轮 20CR2NI4钢 渗碳淬火 减重孔 粗刀痕 裂纹源 

分 类 号：TG156.8[金属学及工艺—热处理]