为了提高国产108 t矿用自卸车齿轮寿命,采用金相显微镜、硬度测试、扫描电镜等试验手段,对108 t矿用自卸车齿轮原热处理工艺进行了研究,分析了非金属夹杂物等级、硬度、淬硬层深度、渗碳层深度、碳化物等级。结果表明:108 t矿用自卸车齿轮原预先正火处理的试样晶粒粗大、夹杂物明显;使用HSFD-2型分级等温淬火油的渗碳淬火试样或者渗碳二次淬火热处理试样在渗碳层组织、淬硬层深度、夹杂物各方面优于使用N32机械油的渗碳淬火试样。 In order to improve gear life of domestic 108 t mining dump truck, the original heat treatment process of 108 t mine dump truck gears was studied by means of metallographic microscope, hardness test and scanning electron microscope. The effects of nonmetal inclusions grade, hardness , Hardened layer depth, carburized layer depth, carbide grade. The results show that the grains of 108 t mine dump truck are pre-normalized with coarse grains and obvious inclusions. The samples hardened by carburizing HSFD-2 graded isothermal quenching oil or carburizing secondary quenched heat treatment In the carburized layer structure, hardened layer depth, inclusions in all aspects better than the N32 mechanical carburizing quenched sample.