17Cr2Ni2Mo变速箱副箱输出轴断裂失效分析  

Analysis on Fracture Failure of 17Cr2Ni2Mo Auxiliary Transmission Output Shaft

作　　者：张涛 ZHANG Tao(Mechanical and Electrical Design and Research Institute of Shanxi Province,Taiyuan 030009,China)

机构地区：[1]山西省机电设计研究院,山西太原030009

出　　处：《材料保护》2020年第7期172-176,共5页Materials Protection

摘　　要：通过扫描电镜、金相组织分析、化学成分检测和显微硬度测试等手段研究了17Cr2Ni2Mo变速箱副箱输出轴断裂失效的原因。结果表明:17Cr2Ni2Mo输出轴属单向弯曲、脆性断裂;17Cr2Ni2Mo输出轴热处理过程中淬火温度过高,回火温度偏低,表面形成了粗大的针状马氏体,且淬火的晶粒粗大,表面脆性增加;输出轴断裂源发生于输出轴轴颈变截面过渡部位,在热处理过程中极易产生表面裂纹并向内部扩展,是整个轴中最为薄弱的区域,建议改进热处理工艺。By means of macro and micro observation,metallographic analysis,chemical composition analysis and micro hardness test,the reason of fracture failure of 17Cr2Ni2Mo auxiliary transmission output shaft was studied. Results showed that the output shaft of 17 Cr2Ni2Mo belonged to unidirectional bending and brittle fracture. During the heat treatment of the output shaft of 17Cr2Ni2Mo,the quenching temperature was too high and the tempering temperature was too low,resulting in the formation of large acicular martensite on the surface. In addition,the hardened grain was large and the surface brittleness increased. Source output shaft fracture happened on the output shaft journal transition variable cross-section area. In the process of heat treatment,the surface crack could easily occur in the transition part of the variable section of the output shaft journal and expand to the inside,which was the weakest part of the whole shaft. It was suggested to improve the heat treatment process.

关 键 词：变速箱副箱输出轴 针状马氏体 热处理工艺 裂纹 断裂分析 

分 类 号：TG115[金属学及工艺—物理冶金]