Abstract: To improve the impact resistance of gears and determine the core influencing factors on gear impact performance, basic technical research and verification of small samples are carried out. This paper mainly uses the Charpy pendulum impact test method to verify the carburizing and carbonitriding heat treatment processes for three common gear steel materials: 20CrMnTiH, 22CrMoH, and 18CrNiMo7-6. Through combined verification, impact energy, macroscopic impact fracture surfaces, and microscopic fracture morphologies are compared. It is finally determined that higher contents of Mo and Ni alloy elements are associated with higher impact energy values and denser macroscopic and microscopic morphologies. The verification shows that the difference in impact resistance between carburizing quenching and carbonitriding heat treatment processes is not significant. The verification conclusions provide theoretical support for the selection of automotive gear materials and heat treatment.

Key words: gear steel; impact energy; carburizing quenching; carbonitriding

摘要： 为提高齿轮的抗冲击能力，确定对齿轮冲击性能的核心影响因素，进行小样基础技术 研究验证。文章主要通过夏比摆锤冲击试验方法，验证 20CrMnTiH、22CrMoH 和 18CrNiMo7-6 三种常见齿轮钢材料的渗碳处理和碳氮共渗处理两种热处理工艺。通过组合验证，对比了冲 击功、冲击宏观断口和微观断口形貌，最终确定 Mo、Ni 合金含量元素越高，其冲击功数值 越高、宏观及微观形貌越致密的特点。最终得出渗碳淬火和碳氮共渗两种热处理工艺的抗冲 击性能差异不明显的结论，为汽车齿轮材料和热处理选用提供理论支撑。

关键词: 齿轮钢；冲击功；渗碳淬火；碳氮共渗