| 摘要 |
PURPOSE:To obtain alumina-based sintered material comprising high-strength uniform crystallite by adding specific fine particles of iron oxide to alumina sol, gelatinizing and sintering. CONSTITUTION:Alumina sol is blended with fine particles of iron oxide having >=28 m<2>/g specific surface area, gelatinized and sintered at 1,100-1,400 deg.C to give the objective sintered material. The fine particles of iron oxide used have <=0.04 mum average particle diameter and >=28 m<2>/g specific surface area value. Fine particles of iron oxide having <28 m<2>/g specific surface area have large particle diameter, crystal size of sintered material is enlarged by adding the fine particles as seed to the alumina sol even by controlling the sintering temper ature and high-quality and high-strength alumina-based sintered materials are hardly obtained. By production of sintered materials, sintered alumina composed of high-stength uniform crystalline can be supplied by sol-gel method on an industrial scale. |
