碳 C :3.70~4.00%

硅 Si:2.15~2.93%

锰 Mn:0.46~0.66%

硫 S :0.010~0.016%

磷 P :0.027~0.035%

镁 Mg:0.027~0.050%

稀土Re:0.026~0.043%

碳当量:4.3~4.6

抗拉强度 σb (MPa):≥450

条件屈服强度 σ0.2 (MPa):≥310

伸长率 δ (%):≥10

硬度 :160~210HB