When talking about industrial zinc plating, people are usually referring to one of three processes. The three common processes are alkaline zinc plating, zinc iron plating and zinc nickel plating. While plating with zinc has benefits in all of its forms, each of these different plating processes has their strengths and unique applications for which they are well-suited.
Zinc Alkaline Plating
One of unique features of alkaline zinc plating is that the deposit is not particularly thick, but it still offers a high level of corrosion resistance. This is particularly helpful in applications where precise tolerances are needed. These coatings are clear, burn free and fine grained. They also tend to be very bright. These are zero-stress deposits that should not cause blistering.
Zinc Iron Plating
This type of zinc plating is typically fine-grained, lightly stressed, and free from burns, even when the current density is unusually high. The deposit usually has 0.4 to 0.8 percent iron by weight. Three additives are used in the process of versatility and flexibility, adding deposit brightness, grain refinement and stability. The additives also allow the iron to be co-deposited, allowing an alloy coating to be created. Items plated by this process tend to have a uniform plate distribution with a low variation in iron content.
Zinc Nickel Plating
If corrosion protection is your primary concern, zinc nickel plating is what you need. The process deposits 12-15 percent nickel fairly consistently as part of the zinc/nickel alloy. The exceptional corrosion protection it offers will even remain in effect after the thermal shock created by leaving the piece in extreme heat for 24 hours.
The deposits created by this process are very bright, blister free, whisker-free (even after bending) and can accept clear or black trivalent passivates easily. The overall adhesion characteristics are excellent, so other forms of final treatment are also easy to apply.
The zinc-nickel plating process is often used as a replacement for cadmium plating. This type of nickel plating can be done using rack or barrel methods and has excellent covering power with uniform distribution. In this plating process, the nickel tends not vary as a function of current density.
Dekalb Metal Finishing can provide plating with zinc in all three of the most popular methods, as well as other metal finishing services. Visit www.dekalbmetal.com to find out more about the range of services they offer.