| 摘要 |
1303877 Ceramics WESTERN ELECTRIC CO Inc 10 April 1970 [14-April 1969] 17149/70 Heading C1J A body comprises a ceramic surface portion having the composition by weight 30À5-40À5 CaO, 59À5-69À5 Al 2 O 3 and 10-20 SiO 2 . The ceramic surface portion is made by mixing oxides or compounds decomposable thereto, calcining the mixture, forming the calcined mixture to shape and firing. The starting mixture is milled as an aqueous or organic slurry in a ball mill, dried granulated and calcined, e.g. at 800-1100‹ C. The calcined material is pulverized, mixed with binding, lubricating or plasticizing additives and an aqueous or organic carrier and ball milled, the ball milled slurry is shaped by dry pressing, extruding or doctor blading on to a carrier substrate (which can subsequently be removed) and then fired, e.g. at 1300-1420‹ C. Electric circuit components are made by sputtering a layer of tantalum on to the surface. |
