A.碳素結(jié)構(gòu)鋼 B.碳素工具鋼 C.優(yōu)質(zhì)碳素結(jié)構(gòu)鋼 D.優(yōu)質(zhì)碳素工具鋼
A.低碳鋼 B.中碳鋼 C.高碳鋼 D.無法判斷
A.低于0.0218% B.在0.0218%~2.11%之間 C.在2.11%~6.69%之間 D.高于6.69%