谐波减速器柔轮与柔性轴承断裂失效分析  

Fracture Analysis on Flexspline and Flexible Bearing of the Harmonic Reducer

作　　者：穆晓彪 邵洙浩 郝春辉 高明艳 张朝磊[2] Mu Xiaobiao;Shao Zhuhao;Hao Chunhui;Gao Mingyan;Zhang Chaolei(Beijing CTKM Harmonic Drive Co.,Ltd.,Beijing 101300,China;School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]北京中技克美谐波传动股份有限公司,北京101300 [2]北京科技大学材料科学与工程学院,北京100083

出　　处：《机械传动》2023年第3期100-104,共5页Journal of Mechanical Transmission

摘　　要：通过观察显微组织、测定力学性能以及观察断口形貌,对比分析国产失效谐波减速器和日本谐波减速器关重件柔轮和柔性轴承的显微组织和力学性能,并分析了国产谐波减速器过早失效的原因。结果表明,失效谐波减速器柔轮显微组织与日本相同,均为回火屈氏体,失效柔轮平均晶粒尺寸为8.2μm,比日本柔轮平均晶粒尺寸高了1.5μm;失效柔性轴承和日本柔性轴承显微组织均为回火马氏体,失效柔性轴承平均晶粒尺寸为13.1μm,比日本柔性轴承平均晶粒尺寸高出6.9μm。失效谐波减速器柔轮断口呈脆性断裂,无明显裂纹源,但失效的柔性轴承断口存在明显断裂走向,在裂纹源中有大尺寸、聚集性分布的夹杂物。失效轴承钢质洁净度差,存在大尺寸夹杂物,且显微组织晶粒粗大,阻碍裂纹扩展的能力差,导致国产谐波减速器过早失效。Microstructure and mechanical properties of the failure flexspline and the Japanese flexspline for harmonic reducers and fracture reason are analyzed by quantitative of microstructure,determination of mechanical properties and fracture analysis.The result shows that the microstructure of the flexspline of the failed harmonic reducer is the same as that of Japan,both of which are tempered troostite.The average grain size of the failure flexspline is 8.2μm,which is 1.5μm higher than that of the Japanese flexspline.The microstructure of the failure and Japanese flexible bearings is tempered martensite.The average grain size of failure flexible bearings is 13.1μm,which is 6.9μm higher than that of the Japanese flexible bearings.The fracture morphology of the flexspline presents brittle fracture characteristics without obvious crack source.The fracture of flexible bearings shows obvious fracture trend.There are obvious crack trends in the fracture of flexible bearing.The crack source is pinpointed at the region where large agglomerative inclusions are observed.The poor purity of flexible bearing and the coarse microstructure with poor ability to hinder crack propagation are the main causes of premature failures of domestic harmonic reducers.

关 键 词：柔轮 柔性轴承 晶粒尺寸 夹杂物 

分 类 号：TH132.46[机械工程—机械制造及自动化] TH133.3