| 摘要 |
PURPOSE:To obtain the subject porous refractory for gas blowing, having excellent spalling resistance, gas permeability, etc., by molding a mixture of magnesia as a main material containing specific amounts of titanium dioxide and fine alumina and sintering. CONSTITUTION:(A) 0.3-10wt.% titanium dioxide of rutile structure and (or) anatase structure is blended with (B) 0.4-15wt.% alumina having <=100mum average particle diameter and (C) the rest of magnesia. Then the prepared mixture of magnesia as a main material is molded and then sintered to give porous refractory for gas blowing. Further blending of <=10wt.% one or more selected from compounds containing cations of Si<4+>, Zr<4+>, Fe<3+>, Mg<2+>, Li<+>, Ni<2+> and Cr<2>+ having the same or larger diameter of cation than that of titanium can prevent reduction in corrosion resistance caused by addition of titanium dioxide. |
