热处理工艺对高速列车用51CrV4钢轴箱弹簧力学性能及服役性能的影响

Influence of heat treatment process on mechanical properties and service performance of 51CrV4 steel journal box spring for high-speed trains

研究了热处理工艺对高速列车用51CrV4钢轴箱弹簧服役性能的影响,确定最佳的热处理工艺,分析了51CrV4弹簧钢在840~900℃淬火及380~520℃回火后的拉伸、冲击性能及疲劳强度演变规律,并建立了基于材质疲劳极限的51CrV4钢轴箱弹簧服役性能评估方法,研究了热处理工艺对弹簧临界服役载荷的影响。结果表明,随着淬火温度的升高,51CrV4弹簧钢的拉伸强度和疲劳强度增加;随着回火温度升高,拉伸强度下降而塑韧性增加。较低淬火温度+较高回火温度下的强度低于TB/T 2211—2018要求,较低回火温度下的冲击性能也接近于标准下限。综合考虑51CrV4钢弹簧的强度和塑韧性,在880℃淬火+460℃回火及900℃淬火+460~480℃回火的工艺范围内其具有较优的服役性能。

Influence of heat treatment process on the service performance of 51CrV4 steel journal box spring for high-speed trains was investigated,the optimal heat treatment process was determined,and the tensile properties,impact properties and fatigue strength evolution of the 51CrV4 spring after quenching at 840-900℃and tempering at 380-520℃were analyzed.The service performance evaluation method for the 51CrV4 steel journal box spring based on material fatigue limit was established,and the influence of heat treatment process on the critical service load of springs was studied.The results show that with the increase of quenching temperature,the tensile strength and fatigue strength of the 51CrV4 spring steel increase.With the increase of tempering temperature,the tensile strength decreases,but the toughness increases.The tensile strength subjected to lower quenching temperature and higher tempering temperature is lower than that of the standard TB/T 22112018,and the impact absorbed energy at lower tempering temperature is close to the lower limit of the standard.Considering the mechanical and service properties of the 51CrV4 steel spring,the optimum heat treatment processes of 900℃quenching+460-480℃tempering and 880℃quenching+460℃tempering are recommended.