| 摘要 |
PURPOSE:To prevent permeation of aluminum melt, to suppress reaction between the aluminum melt and alumina-aluminum nitride-based refractory with and to subdue its contamination, by making the central pore diameter of the refractory, consisting essentially of alumina and/or an alumina refractory material (hereinafter abbreviated as alumina powder) and alumina nitride, into <= a prescribed value. CONSTITUTION:Alumina-aluminum nitride-based refractory consists essentially of 95-35% alumina powder and 5-65wt.% of aluminum nitride and has <=3.0mum central pore diameter. Firstly, the blend is kneaded with a well-known binder for refractory such as a wax-based binder. The particle diameter of the alumina power is not particularly limited. The average particle diameter of aluminum nitride is preferably <=20mum. The kneaded material is molded by press molding. The prepared molded article is dried in the atmosphere at 90-120 deg.C for 10-24 hours and then heated at 0.05-1 deg.C/minute rate of heating to a prescribed temperature corresponding to the kind of the binder to remove the binder. Then, the molded article is burnt at 0.5-3 deg.C/minute rate of heating for 2-3 hours up to a burning temperature determined by the blending ratio of the alumina powder and aluminum nitride. |
