| 摘要 |
860,700. Electro-plating. MUSCHENIG, G., WIRTZ, K., SCHMIDTBERG, M., and OFFERMANNS, H. Jan. 5, 1959 [Jan. 13, 1958], No. 360/59. Class 41. In the process of coating steel or other metal surfaces electrolytically with (1) copper, (2) nickel, and finally (3) chromium, a coating of another metal preferably tin or lead is interposed on the copper coating, whereby the individual coatings may be reduced in thickness. In an example, a steel sheet after degreasing, pickling in HC1, and washing, is coated electrolytically with a copper layer of 25 to 30 microns, using a copper cyanide bath. The plated sheet is then polished to reduce the copper layer to 15 to 20 microns, and after cleaning is plated with lead from a fluoboric acid-lead bath giving a coating of 3 microns. A nickel coating of 10 to 15 microns and a final chromium coating of 0.3 micron is then applied. |
