Electroless nickel plating is a process used to deposit a layer of nickel onto a substrate, such as aluminum, without the need for an electrical current. Unlike electroplating, which relies on an electrical current to deposit the metal, electroless nickel plating is an autocatalytic process that occurs through a chemical reaction.

The substrate, in this case, an aluminum die casting, is thoroughly cleaned and prepared to ensure proper adhesion of the electroless nickel coating. This typically involves degreasing, descaling, and removing any oxide layers from the surface

The prepared surface is then activated using an etching or activation solution. This step helps to promote adhesion and provides a suitable surface for the subsequent plating process.

The activated aluminum component is immersed in a nickel plating bath, which contains a solution of a reducing agent, a source of nickel ions, and other chemical additives. The reducing agent initiates a chemical reaction that deposits a layer of nickel onto the surface of the component.

Once the electroless nickel plating is complete, the component may undergo post-treatment processes such as rinsing, drying, and, in some cases, heat treatment.