| 摘要 |
The surface of a ceramic body is metallised by forming thereon a layer of metal comprising manganese either alone or with a smaller proportion by weight of one or more of molybdenum, nickel, iron, tungsten, chromium and cobalt, and firing the layer in a non-oxidising atmosphere to a sufficient temperature to bond it in position. In a modification, one or more of the metals may be applied in the form of oxide or other compound which is subsequently reduced to the metal on firing in a reducing atmosphere. The layer may be applied as a paint by suspending finely-powdered metals in an organic binder. The binder used in the example is prepared by dissolving pyroxylin in ethyl lactate. The process is applied to the joining of ceramic bodies to metal bodies or other ceramic bodies. Specification 850,190 is referred to.ALSO:The surface of a ceramic body is metallized by forming thereon a layer of metal comprising manganese either alone or with a smaller proportion by weight of one or more of molybdenum, nickel, iron, tungsten, chromium and cobalt, and firing the layer in a non-oxidizing atmosphere to a sufficient temperature to bond it in position. When a plurality of metals are used, the layer initially applied may be a single homogenous coating or may be constituted by a number of sub-layers of different compositions. The metals may be applied (1) by evaporation or sputtering, (2) as a paint by suspending finely-powdered metals in an organic binder, (3) in the form of a foil, e.g. a composite foil made by electroplating one of the metals with one or more layers of other metals, or (4) in the form of oxide or other compound which is subsequently reduced to the metal on firing in a reducing atmosphere. Bodies metallized in this may may be joined to metal bodies or to other similarly metallized ceramic bodies by soldering or brazing. Alternatively, two ceramic bodies may be joined in a single operation by interposing a layer of manganese &c. between two matching surfaces and then firing. The invention is applicable to the joining of ceramic bodies for use as envelopes for semi-conductor devices or, according to the Provisional Specification, in the manufacture of thermionic valves. Specification 850,190 is referred to.
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