| 摘要 |
PURPOSE:To obtain mullite ceramics with a few interstices only on the surface region by coating the entire green sheet surfaces of mullite-based ceramics with tungsten or molybdenum-based conductor paste, forming a printed thin coat, and grinding off the above conductor layer after it is sintered at high temperature. CONSTITUTION:A sintering assistant which comprises 90wt.% SiO2, 7wt.% Al2O2, and 3wt.% MgO is added to 75wt.% mullite's fine powder by 25wt.%. A mold assistant is further added to the powder to obtain a slurry-shaped mixture which is processed by the doctor blade method and a sheet is formed. A thin tungsten layer is formed on this green sheet, coated with tungsten paste. A sintered body is obtained, which comprises a tungsten layer 1 and mullite- based ceramic integrated into one piece by sintering the green sheet on which the tungsten layer is formed. Only the tungsten layer 1 on the surface of the sintered body is ground with diamond splinters. As a result, it is possible to obtain a substrate whose mullite-based ceramic surface alone has a very small number of interstices. |
