| 摘要 |
PROBLEM TO BE SOLVED: To obtain a refractory having excellent creep resistance and spalling resistance by adding a small amount of chromium oxide to a main raw material comprising fused magnesia and seawater magnesia clinker and/or natural magnesia clinker, kneading, molding and sintering the mixture. SOLUTION: A main raw material comprising 20-100 pts.wt. of fused magnesia and 0-80 pts.wt. of seawater magnesia clinker and/or natural magnesia clinker is kneaded with 0.5-3 wt.% of chromium oxide on outer percentage and about 2.5 wt.% of bittern as a binder, molded under about 1,000 kgf/cm2 and sintered at 1,700-1,900 deg.C to give a refractory. The fused magnesia and the seawater and natural magnesia clinkers whole having >=95 wt.% MgO content are used as the magnesia raw materials. Impurities such as CaO, SiO2, Fe2O3, Al2O3, etc., components except MgO should be restricted to <=5 wt.% due to reduction in the melting point of the matrix part of MgO-based refractory and decrease in viscosity. |
