| 摘要 |
<p>1,149,625. Vapour- and electro-plating iridium; powder metallurgy. UNION CARBIDE CORP. June 7, 1966 [Sept.14, 1965], No.25225/66. Headings C7B, C7D and C7F. A graphite substrate is provided with an adherent pore-free coating of Ir by applying a slurry of fine Ir particles (e.g. 1 to 3 micron average size) to the substrate; heating the substrate and particles to produce a sintered Ir coating, preferably first heating at a rate not exceeding 175‹C/hr. in argon up to 400 Œ20‹C. and holding thereat e.g. for 1 hour to vaporize the liquid of the slurry, e.g. xylene, toluene, benzene, alcohol or naphtha, and then heating to 1730-2130‹ C. to sinter; vapour plating the sintered coating with Ir, preferably by bringing it into contact in CO and at 300-800‹ C. with a sublimated Ir (chloro) carbonyl; and electro-depositing an Ir layer on the vapour plated Ir, e. g. from a fused electrolyte of 70% NaCN and 30% KCN containing 6 g/l Ir. The liquid vehicle of the slurry may contain a deflocculent such as cyclopentadiene resin, glycerine, stearic acid or polyvinyl alcohol.</p> |
