汽车变速器齿轮轴的强韧化热处理  

Strengthening and Toughening Heat Treatment of Automobile Transmission Gear Shaft

作　　者：刘文英[1] 

机构地区：[1]通辽职业学院,内蒙古通辽028000

出　　处：《热加工工艺》2017年第4期212-214,217,共4页Hot Working Technology

摘　　要：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 make the 20CrMnTi transmission gear shaft strengthening and toughening, through the improvement of normalizing and quenching process, the heat treatment process, mechanical properties and wear resistance were studied. The results show that compared with the heat treatment process before improvement, for 20 CrMnTi automobile transmission gear shaft, the tensile strength, yield strength and elongation at 25 ℃after heat treatment increase by 8.6%, 7.8%and 30.2%, respectively using improved process; the tensile strength, yield strength and elongation at 350 ℃ increase by43.0%, 64.8% and 57.9%, respectively; the wear volumes at 25 ℃ and 350 ℃decrease by 62.2% and 71.2% respectively. The optimized normalizing process of 20 CrMnTi gear of automobile transmission shaft strength and toughness heat treatment is isothermal normalizing of 875 ℃×1.5 h＋650 ℃×0.5 h and then air cooling. The optimized quenching process is 870 ℃×3.5 h（carbonitriding） then 560 ℃×0.5 h（step quenching）, and then oil cooling.

关 键 词：强韧化热处理 变速器齿轮轴 20CRMNTI钢 力学性能 耐磨损性能 

分 类 号：TG162.71[金属学及工艺—热处理]