Electroless Nickel and Magnetism
Q: We apply electroless nickel to a number of different steel substrates. We routinely demagnetize the parts before placing them in the plating bath. Recently one of our chemical vendors suggested that we were wasting money by doing this since electroless nickel does not seem to be harmed by magnetic substrates. What are your thoughts? P. F.
A: My answer to this question is simple and straightforward: Always demagnetized parts before plating them in any type of plating bath. While it is not likely that magnetism affects the electroless nickel deposit in any way, it certainly can affect the cleaning and preparation processes prior to the plating step. If your part is magnetic, it will attract magnetic particles that may be present in any of the processing baths. Magnetic particles will adhere to the surface and can cause all kinds of problems with roughness and porosity.
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