Nickel Plating Brass and Steel Together
What causes nickel plate peeling when plating both brass and steel parts on the same line?
Q. We plate brass and steel parts on the same nickel plating line because we are space limited. The plating line works well when the cleaners are new, but after a short period of time we start having peeling of the nickel plate from the steel parts. Do you have any thoughts as to what is going on? –L.S.
A. You have a classic problem caused by plating copper-based materials and steels on the same plating line. You most likely have copper in your cleaning tanks, rinse tanks, acid dip and nickel plating baths. Copper forms an immersion deposit on your steel parts. This immersion deposit does not adhere very well to the steel and, as a result, you get peeling. The solution is to install separate cleaners and rinse systems for the steel and brass parts.
To get a better handle on what you are dealing with, I would start out by monitoring the amount of copper present in your cleaners and rinse tanks. You may be able to reduce the severity of the immersion deposits by “going in live” to your plating baths. Improving your rinse steps may also be helpful, but the bottom line is that you will have to separate the cleaners, acid dips and rinses for brass and steel parts.
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