| 摘要 |
PURPOSE:To obtain fine powder of mullite capable of giving a composite ceramic having high strength and toughness, by mixing zirconia sol to mullite sol composed of boemite sol and an aqueous dispersion of amorphous silica, concentrating the obtained mixed sol and drying, pulverizing and heating the resultant gel. CONSTITUTION:Boemite sol and an aqueous dispersion of amorphous silica are mixed together at an Al2O3/SiO2 molar ratio of >=1.5 to obtain mullite sol. The mullite sol is mixed with <=30vol% zirconia sol (in terms of ZrO2) and the produced mixed sol is concentrated until the pH of the mixture reaches <=2. The obtained gel is dried, pulverized and heated to obtain fine powder of mullite having fine particle size and high sintering degree and containing uniformly dispersed t-ZrO2 fine particles. |
