一种大尺寸20CrMnTi渗碳齿轮断裂失效分析  

Fracture Failure Analysis of A Large Size 20CrMnTi Carburized Gear

作　　者：赵祥路 王壮壮 苏广兰 殷凤仕[1] ZHAO Xianglu;WANG Zhuangzhuang;SU Guanglan;YIN Fengshi(School of Mechanical Engineering,Shandong University of Technology,Zibo 255049,China)

机构地区：[1]山东理工大学机械工程学院,山东淄博255049

出　　处：《热加工工艺》2023年第4期160-162,共3页Hot Working Technology

基　　金：淄博市校城融合发展计划项目(2017ZBXC082)。

摘　　要：通过金相分析、化学成分分析、硬度测试、扫描电镜分析等,对一种大尺寸20CrMnTi渗碳齿轮的断裂失效事故进行试验研究。结果表明:齿轮断裂发生在弯曲应力最大的齿根部,在渗碳层发生沿晶断裂,心部为穿晶准解理断裂。齿轮失效的原因是该20CrMnTi钢齿轮尺寸大,齿轮的淬透性不足导致心部不能获得马氏体组织,而是形成了上贝氏体组织,贝氏体组织中的不连续片状碳化物分布在铁素体条间,在应力作用下促进了裂纹扩展,使齿轮最终失效。The fracture failure analysis of a large-size 20CrMnTi carburized gear was carried out by metallurgical analysis,chemical composition analysis,hardness test,scanning electron microscope analysis etc.The results show that,the gear fracture occurrs at the root of the teeth with the largest bending stress.Intergranular fracture occurs in carburized layer and transgranular quasi-cleavage fracture occurs in the core.The cause of gear failure is the large size of the 20CrMnTi steel gear.The insufficient hardenability of the gear results in the formation of the upper bainite structure rather than the martensite structure in the center.The discontinuous sheet carbide in the bainitic structure is distributed among ferrite bars,which promotes the crack propagation under the action of stress and makes the gear failure.

关 键 词：20CrMnTi 渗碳齿轮 沿晶断裂 准解理断裂 上贝氏体 

分 类 号：TG111.91[金属学及工艺—物理冶金] TG162.73[金属学及工艺—金属学]