| 摘要 |
520,005. Alloys; coating metals. STANDARD TELEPHONES & CABLES, Ltd. Dec. 2, 1938, No. 35164. Convention date, Dec. 4, 1937. [Classes 82 (i) and 82 (ii)] [Also in Group XXXVI] A copper cuprous oxide rectifier is made from commercial copper of high purity to which has been added from 0À05 - 0À4 per cent. of lead. Such an alloy is formed into sheets, and blanks and washers punched therefrom and an oxide-coating is produced thereon, for instance by heating at 1000‹C. for 8 minutes in an oxidizing atmosphere, heating at 500‹C. for 5 minutes and quenching in cold water. The resulting oxide layer is heated to provide a low ohmic contact surface thereon, for instance by the process described in Specification 519,987. |
