C

Si

Mn

P

S

Al

N

Cu

Cr

Mo

Ni

Ti

Nb

V

≤0.18

≤0.50

1.10~1.70

≤0.025

≤0.015

≥0.020

≤0.012

≤0.30

≤0.30

≤0.08

≤0.50

≤0.03

≤0.05

≤0.10