| 摘要 |
<p>Platinum or platinum alloy electric heating elements, thermocouples and the like which are subjected to high temperature are coated with a refractory oxide such as alumina or zirconia by flame spraying. A coat of metallic platinum or a platinum alloy may first be applied, also by flame spraying. The surface of the element may be roughened by shotblasting before coating. Specification 745,257 is referred to.ALSO:Platinum or platinum alloy electric heating elements, thermocouples or other electrical conductors for use at high temperatures are flame-sprayed with platinum or platinum alloy as a primer before applying a coating of alumina or zirconia. The surface may be provided with a knurled, scratched or etched finish before spraying. Specification 745,257 is referred to.</p> |
