摘要 |
<p>There is disclosed an electroplating bath for depositing zinc/manganese alloys on a substrate characterized in that it comprises an aqueous bath free or substantially free of ammonium halide and of fluoroborate which is made up from 10-150 g/l, alkali metal salt, 30-90 g/l boric acid, 10-200 g/l water soluble zinc salt, 10-50 g/l water soluble manganese salt, 60-140 g/l alkali metal gluconate or tartrate and a base e.g. an alkali metal hydroxide to bring the pH to the range 6.1-7.1. Passivates are also disclosed.</p> |