C(%):≤0.23
Mn(%):1.65
Si(%):≤0.4
P(%):≤0.04
S(%):≤0.05
V:0.02~0.2
NB:0.015~0.06
Ti:0.02~0.2
AL：≥0.015
Cr:≤0.7
Ni:≤0.7
