| 摘要 |
508,014. Uniting metal to ceramic material; couplings. S I E M E N S - SCHUCKERTWERKE AKT.-GES. Dec. 20, 1937, No. 35268. Convention date, Dec. 19, 1936. [Classes 36 and 38 (i)] [Also in Groups II and XI] To enable a metal member to be soldered or welded to a ceramic body, the latter is metallized by first heating to a temperature at or near and preferably immediately below the fusing point of the metal to be applied and is then coated with the metal by-spraying, e.g. by the Schoop process. The coating applied by spraying may 'be thin and may be thickened by other means, e.g. electrolysis. In the preferred method a non-metallic intermediate layer, e.g. a glaze, is first applied to the ceramic body, this layer having a softening point which lies below the fusing temperature of the metal coating, so that it is softened during the preheating. The softening temperature of the glaze should preferably be above the fusing temperature of the solder to be used in joining the metal member to the metallized ceramic body. The process may be used in manufacturing heating resistances, e.g. for electric ovens, the heating conductor being surrounded by a ceramic tube rendered gas-tight by baking and which is metallized by the process described to enable motal end seals or closing members to be joined thereto in a gas-tight manner. It may also be applied to the production of gas-tight seals for ceramic vacuum vessels, e.g. discharge tubes or vacuum switches. The Specification as open to inspection under Sect. 91 described also the construction of heating elements for electric ovens, including the means for coupling the resistance element to the terminal, which forms the subject-matter of Specification 507,846. This subject-matter does not appear in the Specification as accepted. |
