A.轉(zhuǎn)爐鋼、平爐鋼、電爐鋼 B.結(jié)構(gòu)鋼、工具鋼、特殊鋼 C.普通鋼、優(yōu)質(zhì)鋼、高級優(yōu)質(zhì)鋼 D.碳素鋼、合金鋼
A.72h±30min B.72h±45min C.72h±1h D.72h±3h
A.240N/s±20N/s B.2400N/s±200N/s C.50N/s±10N/s D.50N/s±5N/s