| 摘要 |
1,270,433. Coating with metals; electroplating. CHROMALLOY AMERICAN CORP. April 14, 1969 [May 31, 1968], No. 19020/69. Headings C7B and C7F. A ferrous article is coated with Zn and an outer layer of Al, Cd, Ni, Pb or Co, the Zn being diffused into the Fe and the coating metals being interdiffused. Both metals may be applied in a pack diffusion process or one metal may be applied by electrolytrically and the other by pack diffusion. The coatings may be subsequently heated. Zn may be applied by pack diffusion, Ni electro-plated and then an outer layer of Zn applied by pack diffusion under such conditions that the Zn diffuses through the Ni or the first layer of Zn may be omitted. The Cd may be electro-plated from a conventional cyanide bath, and the Ni from a conventional nickel sulphamate bath at a current density of 0À4 amps/sq in. |
