| 摘要 |
<p>A steel sheet is subjected to an electro-galvanizing treatment in a Zn-ion based acidic galvanizing bath containing one additive selected from the group consisting of: (a) Cr3+ ........................ 50 - 700 ppm, (b) Cr6+ ........................ 50 - 500 ppm, and (c) Cr3+ and Cr6+ ............... 50 - 700 ppm, in which Cr6+ being 500 ppm at the maximum; and at least one additive selected from the group consisting of: (d) Sn ion ...................... 10 - 5,000 ppm, and (e) In ion ...................... 10 - 3,000 ppm. Then the electro-galvanized steel sheet is subjected to a conventional chromate treatment. By this procedure, the adaptability of the electrogalvanized steel to chromating is improved.</p> |
