目的 研究常用的减速机高速工作中，材料为17CrNiMo6齿轮轴断齿现象的原因以及改进措施。方法 通过化学成分分析、硬度检测、显微组织分析等方法，研究分析17CrNiMo6齿轮轴断齿现象的原因，并根据产生断齿的原因提出改进措施。结果 17CrNiMo6齿轮轴断裂为疲劳断裂，断齿的主要因素为调制热处理工艺不当、非金属杂物超标产生应力集中现象等。结论 通过改进热处理工艺、优化结构设计、提高加工精度等措施可改善17CrNiMo6齿轮轴的断齿现象。

The work aims to study the causes for the tooth breaking of 17CrNiMo6 gear shaft in the high-speed work of the commonly used reducer and the improvement measures. The causes for the tooth breaking of 17CrNiMo6 gear shaft were studied and analyzed by means of chemical composition analysis, hardness test, microstructure analysis and other methods. The improvement measures were proposed according to the causes for tooth breaking. The results showed that the factors such as the fatigue fracture, the improper preparation of heat treatment process and the stress concentration caused by nonmetallic debris that exceeded the standard were the main causes for the tooth breaking of 17CrNiMo6 gear shaft. By improving the heat treatment process, optimizing the structure design, improving the processing accuracy and other measures, the tooth breaking of 17CrNiMo6 gear shaft can be improved.