The fracture morphologies and the microstructure of the broken gear for gear reducer were examined by scanning electron microscope. It can be concluded that main reason to result in the fracture of the gear is that the remains tensile stress and ferrite in the foot of gear resulting from unreasonable heat treatment, scratch of gear hobs and the roughness surface of the gear.% 采用扫描电镜对减速器齿轮断齿分别对断口形貌以及夹杂物进行了观察和微区成分分析，原热处理工艺不合理导致齿轮根部未淬火、硬度分布不均、根部存在残余拉应力及块状铁素体，同时齿轮根部加工不良，滚齿刀痕明显是导致齿轮断齿的主要原因。针对齿轮失效原因，提出了改进措施，有效避免了齿轮断齿现象的发生。
展开▼
