为了使20CrMnTi汽车变速器齿轮轴强韧化,通过改进正火和淬火工艺,对其热处理工艺、力学性能和耐磨损性能进行了研究。结果表明:与改进前热处理工艺相比,采用改进工艺热处理后的20CrMnTi汽车变速器齿轮轴的25℃抗拉强度、屈服强度和断后伸长率分别提高8.6%、7.8%和30.2%;350℃抗拉强度、屈服强度和断后伸长率分别提高43.0%、64.8%和57.9%;25℃和350℃磨损体积分别减小62.2%、71.2%。优化的20CrMnTi汽车变速器齿轮轴强韧化热处理的正火工艺为:875℃×1.5h+650℃×0.5h后空冷的等温正火处理,优化的淬火工艺为:870℃×3.5h碳氮共渗后先560℃×0.5h分级淬火后油冷。 In order to strengthen and gear the gear shaft of 20CrMnTi automotive transmission, the heat treatment process, mechanical properties and wear resistance were studied by improving the normalizing and quenching processes. The results show that the tensile strength, yield strength and elongation at break of the 20CrMnTi gearbox after heat treatment are improved by 8.6%, 7.8% and 30.2% respectively at 25 ℃ and 350 ℃ The tensile strength, yield strength and elongation at break increased by 43.0%, 64.8% and 57.9% respectively. The wear volume decreased by 62.2% and 71.2% at 25 ℃ and 350 ℃ respectively. Optimized 20CrMnTi automotive gear transmission shaft toughness heat treatment normalizing process is: 875 ℃ × 1.5h + 650 ℃ × 0.5h after isothermal normalizing air cooling, the optimization of the quenching process: 870 ℃ × 3.5h carbon-nitrogen After the first seepage 560 ℃ × 0.5h oil quenching classification quenching.