One of the most popular and effective types of zinc plating is zinc nickel alloy plating. This plating is particularly popular for use in the electronics and automotive industries. It can be applied in a couple of different ways and it provides numerous benefits to the piece being plated. There are also a number of post-plating treatments that can be applied to make the coating even more effective.
About Zinc Nickel Alloy Plating
Zinc nickel plating adds a protective coating to a metal. The coating will consistently add 12 to 15 percent nickel by weight in addition to the zinc, giving a piece excellent corrosion resistance. This coating is a good replacement for cadmium for use in electronic devices. Zinc Nickel Plating is the preferred plating method for auto parts by a number of automotive manufacturers, including GM, Ford, Chrysler, Honda, and Toyota, among others.
Plating Methods
Zinc nickel plating can be applied using either the rack or barrel plating methods. Both methods involve submerging the part or parts to be plated in an electrolyte bath while attached to a cathode with an anode or anodes separate but in the bath. The rack method keeps the piece stationary on a jig, while the barrel method, a method more suitable for smaller parts, has the parts tumbling in a non-conductive barrel or cage.
Zinc Nickel Plating Benefits
Zinc nickel alloy plating adds excellent corrosion resistance with minimal variation of nickel content or plate distribution, regardless of current density. The deposits maintain a burn-free appearance, even when the current densities are high. The deposits also do not suffer from “whiskering” when a plated piece is bent. The coating is generally blister free and it had excellent adhesion qualities that allow for a variety of post-plating treatments.
Post Plating Treatments
After plating is completed, the zinc nickel deposits are usually passivated, which increases the corrosion resistance of the piece even more. After passivation, you may also choose to add a topcoat. Depending on the type of topcoat you choose, it may add predictability to the torque and tension characteristics of the piece, improve corrosion resistance or improve resistance to heat exposure.
Dekalb Metal Finishing can perform zinc nickel plating as well as other forms of finishing for you. To learn about their range of services, visit www.dekalbmetal.com.
