不同冶炼方法对扭杆弹簧钢超高周疲劳性能的影响

摘要：以一种新型扭杆弹簧用高强钢（代号N1）为研究对象，采用真空自耗(VAR)和电渣重熔(ESR)冶炼方法制备得到2种实验钢（N1 VAR、N1 ESR）。研究了VAR、ESR冶炼方法对实验钢洁净度和超高周疲劳性能的影响。结果表明：采用电渣重熔工艺冶炼的N1 ESR试验钢中氧的质量分数为9×10-6，而采用真空自耗冶炼工艺的N1 VAR试验钢中氧的质量分数仅5×10-6，N1 VAR中氧化物夹杂数量和尺寸减小，夹杂周围裂纹萌生驱动力减小，超高周疲劳强度较高，疲劳寿命增加。

Effect of different smelting methods on very high cycle fatigue properties of a torsion bar spring steel

A new high strength torsion bar spring steel (code N1) was taken as the research object. Two types of experimental steels(N1 VAR and N1 ESR) were prepared by vacuum consumable electrode melting (VAR) and electroslag remelting (ESR) methods respectively. The effect of VAR and ESR smelting methods on the cleanliness and very high cycle fatigue properties of experimental steels was studied. The results show that the oxygen content in the N1 ESR test steel is 9×10-6, while that in the N1 VAR test steel is only 5×10-6. The oxide inclusion size and quantity were reduced due to the low oxygen content in the N1 VAR tests steel, and the driving force for crack initiation around the inclusion is reduced, leading to higher very high cycle fatigue strength and increased fatigue life.