EN Coating and Chemical Resistance

Q. Is an electroless nickel coating chemically resistant to a solution of cyanide? C.O.

A. The chemical resistance of an electroless nickel coating depends on the makeup of the coating and the solution concentration that it is exposed to. Generally speaking, electroless nickel coatings that are rich phosphorus usually have lower rate of material loss compared to those that have a low concentration of phosphorus. Some data that I found indicates that an electroless nickel coating containing approximately 12 percent phosphorus when exposed to a 5 percent solution of sodium cyanide will lose less than 12.5 microns per year.

Additional information about the chemical resistance of various types of electroless nickel solutions can be found in the book “Electroless Nickel Plating” by Wolfgang Riedel. While the book is more than 20 years old, it is still an excellent source of information on EN. The book is available on Amazon.