| Imiting gold plating adjusts the price and ornament conflict,so many ornament adopt imiting gold plating.Imiting gold plating keep golden face , reduce price. At present imiting gold plating apply for many field for example headgear,wristwatch and so on.Formerly imiting gold plating use mainly cyanide,but cyanide is virulent substanc e,cyanide decompound easily in the enviroment It's baleful for operational people.So i t's modal to empolder a sort of harmless and steady plating technics. The imiting in cyanide free bath unuse cyanide, also achieve uniformity imiting purpose. Pating Cu-Z n alloy in cyanide free bath use KNaC4H4O.6H2O as main salt, NaOH and K3C6H5O7. H2O as complexant, and Cu and Zn as alloying metal in the form of cyanide free co mplex. The technological formulation is determined to be composed of KNaC4H4O.6H2 0 80～100g/L,CuSO425～40 g/L,ZnSO410～15 g/L,K3C6H5O7.H2O 20～30 g/L,K H2PO420～25 g/L,NaOH 20～30 g/L and some brightener. And the operational condi tions are suggested as pH value 12～13, operating temperature 30～40℃, cathode curren t density 3～4A/dm2, mechanical agitation.The results show that the coating has properties of golden color, uniformity, nicet y, gradeⅡbrightness, high microhardness,and good adhesion, according with 18K sta ndard. The bath has properties of stable solution, well throwing power and covering p ower.Tartaric acid is used as main complexing agent.which can decrease the toxicity and danger of the bath. The bath has harmless and it is easy to operate and treat wasteresidue.In order to improve the stability of cyanide free bath and the brightness of the coating,effects of stabilizing agent and brightener on the bath and the coating are investigated. The results show that bath stability and coating brightness have been improved in some extent when stabilizing agent and brightener are added.Imating gold coatings obtained from cyanide free bath have brightly golden color and other excellent properties and can be applied to decorative coating.
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