Zinc Alloy Die Casting cyanide alkaline copper plating technology

In China, due to administrative reasons, non-cyanide alkaline copper plating in the past have focused on the research and development of the single plated kinds around the use of large-scale production process support seldom, thus limiting its popularization and application . In particular, the binding force in the non-cyanide alkaline copper plating zinc die castings has not effectively addressed. By experimental and production applications, the SF-628 non-cyanide alkaline copper plating zinc alloy die castings and the Company plating pre-treatment process, excellent adhesion to further promote the accumulation of cyanide alkaline copper process rewarding experience.
The zinc alloy SF-628 non-cyanide alkaline copper combine to force
We know that the cyanide copper plating solution contained cyanide is a very strong complexing agent, but it is also an extremely effective detergent activator in a considerable extent, it can make up for the pre-treatment of the zinc alloy die castings bad implementation, cyanide copper plating liquid even diffusion coating to the substrate surface is very fine shrinkage intergranular gap, by contrast, SF-628 non-cyanide alkaline copper without strong chelating agent, and therefore more easily lead to zinc die castings combined force undesirable phenomena. To improve its binding force, combined with the successful experience of the domestic from the following aspects:
First, improve the the substrate plating applicability of zinc die castings This includes the selection of qualified quality alloy composition zinc aluminum casting materials, advanced mold making and casting process, reliable grinding and polishing process, the surface of dense finish of the workpiece, which can effectively improve zinc aluminum castings surface coating adhesion.
Second, adopt the efficient plating Activation process: preferred zinc alloy castings mild, efficient chemical process of electrolysis degreasing detergent. Appropriate to introduce the anode electrolytic degreasing, there is a lot of help to improve its binding force, the anode electrolytic degreasing can effectively eliminate past cathode the electrolytic degreasing due to hydrogen evolution caused by foam coating of zinc die castings. Secondly, the appropriate anode electrolytic degreasing excellent ability to remove the part surface fouling, hanging gray, can greatly increase the binding capacity of the copper plating zinc casting surface.
Third, strict process management, process control: SF-628 non-cyanide alkaline copper plating solution is more sensitive to impurities, excessive accumulation of inorganic, organic impurities could easily lead to poor coating adhesion. Therefore, the operation to reduce the amount of impurities into recurring impurity removal operations are not to be ignored. In addition, the process parameters of the bath should regularly analyze adjusted to the optimum range.