CURRENT DISTRIBUTION RATIO AND METAL DISTRIBUTION RATIO IN NICKEL PLATING BATHS

It is shown that the current distribution ratio (CDR) generally increases with increase in current density, possibly due to changes in cathodic polarization. This is supported by the electrochemical characteristics of different baths in the light of Gardam formula. MDR vs I and CDR vs I plots were similar. The values of MDR calculated from the CDR vs I curves and the individual cathodic efficiencies were in good agreement with the experimental values. Wesley bath had the lowest CDR and MDR (i. e. , the highest throwing power). Increase in the nickel chloride content of Watts bath caused a decrease in CDR and MDR and increase in cathodic efficiency and conductivity of the solution.