Abstract: The new energy automobile motor shaft made of non-quenched and tempered steel 50MnSiV (/% ：0.50C, 0.52Si, 1.20Mn, 0.010P, 0.025S, 0.15Cr, 0.10V, 0.015Ti, 0.015N) by eliminating traditional carburizing heat treat¬ment, straightening and finishing process of steel 20CrMnTiH, can not only improve 95% materials utilization rate and 2 delivery days and can also reduce 25% costs. With tensile strength 1100 MPa, yield strength 858 MPa and impact energy 48 J, its static torque (4697 Nm),fatigue life ( ±1600 Nm bidirectional torsion 120 ,000 times, ± 1400 Nm bidirectional torsion 270,000 times) increased by 27% and 93% 〜140% respectively than that of carburized 20CrMnTiH motor shaft, and its performance index and 80,000 km road test results meet motor shaft technical requirements.

摘要： 非调质钢50MnSiV(/%:0. 50C,0.52S,1.20Mn,0.010P,0.025S,0.15Cr,0.10V,0.015Ti,0.015N)制造的新能源汽车电机轴,省去传统调质钢20CrMnTiH渗碳热处理和矫正精整工序,不仅可提高材料95%利用率和2天交货周期,还可以降低25%成本。50MnSiV钢抗拉强度1100 MPa、屈服强度858 MPa、冲击功48J。其静扭扭矩(4697 Nm)、疲劳寿命(±1600 Nm双向扭转12万次、±1400 Nm双向扭转27万次)较渗碳20CrMnTiH钢提高了27%和93%～140%,并且其性能指标和8万公里的路试结果均满足电机轴的技术要求。

关键词: 非调质钢, 50MnSiV, , 20CrMnTiH, 渗碳处理, 电机轴