A.1630~1850 B.1680~1900 C.1570~1890 D.1550~1780
A.0.5~0.8 B.0.4~0.6 C.0.25~0.30 D.0.45~0.55
A.中性耐火材料 B.非氧化物耐火材料 C.堿性耐火材料 D.酸性耐火材料