Abstract: The structure of high stength-toughness spring steel 38SiMnVB -0.39C,1.48Mn,1.21Si,0.09V, 0.0019B was pearlite + ferite with grain size less than No 10,HRC value 26,tensile strength 925～1010 MPa and elongation 45%～58% by finishing rolling between 750 ℃ and 820 ℃ with finished temperature 700~720 ℃ than slow cooling.After rolled it could be cold drawn directly.With 870 ℃ quenched and 320 ℃ tempered the super-fine grain spring steel 38SiMnVB as a spring for cars had excellent comprehensive mechanical properties-tensile strength 2030～2140 MPa,yield stength 1900~2010 MPa,elongation 12%～15%,reduction of area 48%～55%.

Key words: Super-Fine Grain Spring,Spring Steel 38SiMnVB, Controlled Rolling, High Srength-Toughness

摘要： 高强韧性弹簧钢 38SiMnVB(% :0.39C ,1.48Mn ,1.21Si ,0.09V ,0.0019B)经750～820℃温度精轧 ,终轧温度700～720℃轧后缓冷 ,控制轧制后得到的组织为珠光体 +铁素体 ,晶粒度≥ 10级 ,HRC硬度值26 ,抗拉强度 925～1010 MPa ,延伸率45 %～58% ,可以直接进行冷拔。经控制轧制的轿车弹簧用超细晶粒38SiMnVB弹簧钢经 870℃淬火 ,320℃回火后具有极好的综合力学性能 :抗拉强度 2030～2140 MPa ,屈服强度1900～2010 MPa ,延伸率12 %～15 % ,断面收缩率48%～55 %。

关键词: 超细晶粒, 38SIMnVB 弹簧钢, 控制轧制, 高强韧性