| 摘要 |
PURPOSE:To improve oxidation resistance by impregnation treating a refractory, obtained by kneading each of a specific quantity of an Al2O3 fire-proofing raw material, a SiC fire-proofing raw material and graphite, molding and firing in a non-oxidizing atmosphere at a prescribed temp., with Mg alkoxide. CONSTITUTION:The Al2O3 fire-proofing raw material of 60-90 pts.wt. (hereafter pts.) having >=95% purity, the SiC fire-proofing raw material of 5-20 pts. having >=90% purity and graphite of 5-20 pts. having >=90% purity where particle diameter of these raw materials is <=150mum are compounded. As the oxides having <=150mum particle diameter, 1.5-10 pts. sum total of a metallic powder high in fire resistance and a glass powder low in softening point are added and mixed into the powdery compound of 100 pts. Next, the mixture is kneaded, molded and is fired in the non-oxidizing atmosphere such as Ar at >=600 deg.C. After that, Mg-alkoxide is impregnated into the fired material, uniformly dispersed inside of the fired material and heat treated to form MgO which forms a magnesium-aluminum spinel by allowing to react with Al2O3 in the fired material and the carbon-containing refractory excellent in corrosion resistance and oxidation resistance is obtained. |
