摘要 |
A pre-treating solution for electroplating zinc alloy surface contains copper ions, hydroxyl ions, a complexing agent and an additive, wherein the additive is selected from sodium phosphate, sodium hypophosphite, phosphoric acid and dissolvable salts of phosphoric acid. The zinc alloy is dipped in the pre-treating solution and electroplated with a copper coating layer. Then, the zinc alloy is further dipped in a copper sulfate solution for thickening the copper coating layer and lastly coated with an anti-corrosion metal layer. Thereby, zinc alloy has excellent anti-corrosion and anti-wearing efficiency and varnish appearance. Moreover, the pre-treating solution contains no cyanide and thus is low toxic and safe to operator during electroplating and to environment after discharging.
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