A.0.8% B.0.08% C.8% D.0.008%
A.碳素工具鋼 B.碳素結(jié)構(gòu)鋼 C.優(yōu)質(zhì)碳素結(jié)構(gòu)鋼 D.含碳量為T的鋼
A.230MPa B.270MPa C.770MPa D.500MPa