We all know that in the production process of using chemical nickel plating additives for aluminum workpieces, zinc precipitation water needs to be used for zinc precipitation, so that the adhesion of the chemical nickel coating after zinc precipitation is better. However, many customers are still unclear why the workpieces need to undergo secondary zinc precipitation.
Based on on-site experience and the characteristics of Ni-809, a chemical nickel plating additive, and BC-22, a zinc precipitation water, Bigley Technology conducted an analysis. Generally, aluminum alloy workpieces have a thicker and darker film layer after a single zinc precipitation, a rougher crystalline layer, and a much weaker bonding force compared to secondary zinc precipitation, which is not very uniform. However, after secondary zinc precipitation, the film layer of the workpieces is close to gray, and the crystallization is uniform and fine, and relatively thin, This way, the workpiece has good adhesion after chemical nickel plating.
Bigley engineers suggest customers to use two zinc deposits to improve the adhesion of the coating even for aluminum alloy workpieces of different materials. For workpieces made of aluminum profiles, two zinc deposits are required because the adhesion of the film layer after one zinc deposit is not very good, and the time required for zinc deposit is relatively long; The surface of the workpiece made of die-casting aluminum is relatively loose, and the film layer after one zinc deposition will be very black. The reaction liquid between the workpiece and the zinc precipitation water is more intense, and the appearance quality is relatively poor. Therefore, the liquid needs to undergo a second zinc deposition.
So, the above is the reason why aluminum alloy workpieces need to undergo two zinc deposits during the production process using chemical nickel plating additives. When using Bigley's chemical nickel plating additive Ni-809 and zinc precipitation water BC-22 together for production, it can ensure good adhesion of the workpiece coating and effectively improve production efficiency. If you are interested in chemical nickel plating additives, please contact Bigley customer service to obtain free samples and detailed technical information!
If you want to learn more about chemical nickel, you can click to view the "Electroplating Encyclopedia".