A.0.30% B.0.25% C.0.030 D.0.045%
A.Q460 B.T7 C.T10A D.T8
A.碳素結(jié)構(gòu)鋼 B.低合金高強度結(jié)構(gòu)鋼 C.碳素鑄鋼 D.碳素工具鋼