What is Electroless Nickel?

Electroless Nickel plating is a process that deposits nickel on a surface without electric current. Electroless nickel plating is accomplished using a controlled chemical reaction instead of external electrical current to deposit the nickel coating. Another term for electroless nickel plating is autocatalytic nickel plating because there is a catalyst present that allows the reaction to occur.

Nickel and phosphorous electroless nickel baths contain constituants such as nickel ions, hypophosphite, buffers, and complexing agents. The nickel ions combine with phosphorous during the plating process to form the nickel deposit. The hypophosphite is the reducing agent that is the catalyst for chemical reduction of nickel ions. Buffers maintain the pH of the bath, and complexing agents maintain the nickel ions in soluble form. In addition, they both stabilize the bath and help maintain a steady plating rate. The chemical reaction for a typical Nickel Phosphorous plating process is:

The main feature of electroless plating as compared to electroplating is distribution of the plating on the surface of the part. Electroplating relies on current density. The electrical current must be distributed across the surface as evenly as possible. Sharp edges, recesses, holes, threads or other such features will not plate evenly. Through chemical oxidation and reduction reactions an even uniform coating is deposited on a variety of surfaces. There is no edge build-up as with electroplating.

Electroless nickel plating is available in many alloy forms. Contact Hi-Tec Plating, Inc. to see which electroless nickel plating process is best for your application.