| 摘要 |
<p>616,812. Asymmetrically-conducting resistances. STANDARD TELEPHONES & CABLES, Ltd. Feb. 8, 1946, No. 3986. Convention date, March 12, 1945. Drawings to Specification. [Class 37] A method of manufacturing a selenium rectifier element containing a base-plate having a selenium layer comprises applying a first heat treatment at 120‹ C. under pressure, then a second heat treatment without pressure at a higher temperature, but below the melting point of selenium, e.g. about 214‹ C., and a third heat treatment at a temperature of 300-450‹ C., preferably for 2-3 seconds and preferably in an atmosphere of carbon dioxide with or without cooling of the selenium layer between the heat treatments. An apparatus is shown comprising a conveyer belt passing through heated chambers.</p> |
