| 摘要 |
<p>The surface of the electrode is roughened by sand blasting. Following etching, the diamond layer is formed on the electrode body. The etching is non-oxidative and removes more than 5 mu m of material below the roughened surface. The etching rate is 5-15 mu m/h. For etching, concentrated phosphoric acid (exceeding 70%) is used at a temperature of preferably 150[deg] C - 160[deg] C. 85% phosphoric acid is used. Complex builders are added. Etching removes 15-25 mu m. Etching duration is 1.5-2.5 h. During etching, the acid is made up to maintain a desired concentration and given tolerances of the etching process. The electrode body is niobium. It is alternatively tantalum, tungsten or titanium. An independent claim IS INCLUDED FOR the diamond electrode so produced.</p> |
