| 摘要 |
PURPOSE:To improve mechanical strength by molding a mixed powder of MgO powder consisting of cubic primary particles and isometric primary particles and granular ZrO2 powder in a specific weight ratio and burning the molded article. CONSTITUTION:70.0-99.5wt.% MgO powder having >=99.9% purity consisting of 30-60wt.% cubic primary particles having 0.1-1.0mum particle diameter and the rest of isometric primary particles having <=0.1mum particle diameter is blended with 0.5-30.0wt.% granular ZrO2 powder having >=5m<2>/g specific surface area, <=0.5mum average particle diameter and >=99.9% purity. Then the mixed powder is press molded, the molded article is sintered at 1,240-1,400 deg.C to give a tetragonal system-ZrO2 particle dispersion-type sintered material of MgO having <=20% porosity and fine structure wherein >=80% tetragonal system-ZrO2 particles are dispersed and exist in grain boundary. |
