| Because of the excellent tenacity and ductibility, the good electric conductivity and thermal conductivity, the low porosity, and the noblest color, copper plating is mainly used as bottom or middle tier in the nickel plating, tin plating, silver plating and gold plating, to improve the adhesion and corrosion resistance between the base metal and coating. The copper plating also can be applied to the field of decorative or electronics industry.Traditional MN brightener is the development of one of the first acid copper brightener. This brightener has many problems, such as the narrow brightening area, low radiance and no brightness is the low current region. So, this process is difficult to meet the needs of complex parts, precision electroplating. But the study abroad starts early study and some companies have occupied a big domestic market.Aiming at the problems of traditional MN brightener, we have developed a set of new acid copper brightener on the basis of the traditional one. We mainly found an excellent walk agent which is used in the low current densities, and the agent can greatly improve coverage and brightness in the low current densities of acidic bright copper plating.This study developed the composition of brightener by conducting orthogonal experimental.for the composition of single-factor experimental We study the current, temperature of the brightener and discuss the content of copper sulfate and chloride concentration. We found the best mixing and drying conditions to select the optimal process. And we make use of the hull cell, method of cavity, metallographic microscope, coulomb meter to test the performance of the appearance of the coating and the plating liquid. By determining the cathodic polarization curves about the additives, we discussed the impact about the additive.We found that the plating liquid had an excellent throwing power. By using the hull cell, we discovered clad layers were all light. We tested the ability of coverage and found that the coverage is 90%. Meanwhile, the technology also has good dispersing capability and the capability can be 52%. Coating appearance can reach 90 °. Through the metallographic microscope we observed the roughness of surface and found that the coating has corrosion resistance, adhesion and heat resistance can also be comparable with foreign products.Through all kinds of experiments, we finally confirmed the optimum compose and process conditions:H2SO4, process parameters:30～60 ml/L, the best parameters:50 ml/L; CUSO4·5H2O, process parameters:160～220g/L, the best parameters:180 g/1; Cl", process parameters: 20-120mg/L, the best parameters:60 mg/1; H1, process parameters:0.0002～0.001 g/L, the best parameters:0.0004 g/1; SP, process parameters:0.01-0.02g/L, the best parameters:0.016 g/1; P, process parameters:0.05-0.2g/L, the best parameters:0.1g/L;OP-21, technical parameters: 0.005～0.02g/L, the best parameters:0.02g/L; 176 additives, process parameters: 0.0002-0.0008g/L, the best parameters:0.0004g/L; complex dyes, process parameters: 0.1～0.2ml/L, the best parameters:0.15ml/L; temperature 10～35℃, optimum temperature is 25 ℃; anode has some phosphorus; current is 2A; mixing method is bubbling with air.
|
PDF Full Text Request