Environmentally friendly electroplating solutions are formulated with electrolytes containing plating metal ions. During electroplating, the anode metal dissolves in the solution as cations, which migrate to the cathode. These ions gain electrons at the cathode and are reduced to metal, coating the metal product to be plated.
Key performance indicators of the plating solution include dispersibility and plating depth. Dispersibility refers to the plating solution's ability to distribute the coating thickness evenly, also known as uniform plating ability. Plating depth refers to the plating solution's ability to deposit a coating in deep recesses of complex parts, also known as covering ability. Dispersibility only affects the uniformity of thickness, while plating depth only affects whether a coating can be deposited in deep recesses.
Electrochemical parameters of the plating solution include resistivity, conductivity, and cathodic polarization. Resistivity is represented by ρ, and conductivity is the reciprocal of resistivity. Cathodic polarization Δϕk is the slope of the cathodic polarization curve. Conductivity is affected by factors such as conductive salts and pH, while cathodic polarization is related to the formulation of additives and complexes used in electroplating.
Density is a crucial physical parameter affecting the component ratio, deposition rate, and coating uniformity in the electroplating process. Density analysis encompasses testing items such as density measurement, specific gravity testing, and chemical composition analysis. The testing scope includes various electroplating solutions such as nickel plating solutions, copper plating solutions, and zinc plating solutions. Testing is based on international standards such as International Standard 1019-18 and International Standard 1183-1:2019, as well as national standards such as GB/T 20975-2020 and GB/T 1033.1-2021.
