The Influence of Effective Parameters on Optimizing the Electrochemical Deposition Rate of Au-Cu Alloy with High Thicknesses for the Production of Hallow Gold-Jewelry Artifacts with Pulsed Current (PC) on A Silver Substrate

The impact of effective parameters on the electrochemical deposition rate optimization of Au-Cu alloy at high thicknesses on the silver substrate was investigated in the present study. To have co-deposition of gold-copper alloy with the cartage of 18 K (750 ppt) and appropriate deposition rates values of 6mAcm2,6grlit , 55grlit , 24grlit, 66 ˚C, 12.3, 100 rpm and 1mllit, the specified parameters in this method, including current density, ions concentrations of gold, copper and cyanide, temperature, pH, agitation and additive concentration were effectively optimized by the "one factor at a time" method. Scanning electron microscopy (SEM) and surface chemical analysis system (EDS) were used to study the effect of deposition on the cross-sections of the formed layers. The results showed that under the optimum conditions obtained at about 18K, the average current density (Iavg=0.6mAcm2) and a duty cycle (30%) at the same time, the deposition rate was 0.841μmmin and in this method, that was significantly higher than the commercial methods. It should be noted that in a pulsed electrodeposition, with increasing percentages in duty cycle, the deposition rate of the layers was reduced, which can be explained by the reduction of the double layer thickness due to shortening of the pulse off-time.