| 摘要 |
424,442. Glass - ceramic joints. PORZELLANFABRIK KAHLA, Kahla, Thuringia, Germany. Nov. 23, 1933, Nos. 32801 and 32802. Convention dates, Nov. 23, 1932 and July 31, 1933. [Class 56] [See also Group X] Ceramic bodies such as porcelain to be fused to glass in an oil- and air-tight manner are chosen so that the coefficient of expansion of the ceramic body is greater than that of the glass, for example, 10 to 30 per cent greater. Suitable materials for the ceramic body are pure silicates containing magnesium, such as those known under the Registered Trade Mark " Calit," and the trade name " Calan." Or the ceramic article may consist of sintered ceramic materials available as mixtures of aluminium silicates and aluminium oxides free from steatite, the coefficient of expansion of which is 2- 5 + 10<-6> or less, and that of the glass 1À75 + 10-‹ to 2À2 + 10-<6>. The ceramic materials mentioned have a small dielectric loss and a low electric conductivity.
|
