化学成分
C：≤0.18
Si：≤0.50
Mn：≤1.70
P：≤0.030
S：≤0.025
Nb：≤0.07
V：≤0.15
Ti：≤0.20
Cr：≤0.30
Ni：≤0.50
Cu：≤0.30
N：≤0.012
Mo：≤0.10
Al：≥0.015
C：≤0.18
Si：≤0.50
Mn：≤1.70
P：≤0.030
S：≤0.025
Nb：≤0.07
V：≤0.15
Ti：≤0.20
Cr：≤0.30
Ni：≤0.50
Cu：≤0.30
N：≤0.012
Mo：≤0.10
Al：≥0.015
