Plating is a technique using metal to protect and enhance a component by coating the surface. This process lends the component some of the qualities of the metal it has been plated with, which can including corrosion resistance, durability, strength, hardness and even aesthetic value. There are a variety of plating techniques, with the most common being electroplating and electroless plating, particularly the increasingly popular electroless nickel plating.
Electroplating is named for its use of electricity, with a current applied to the component, which creates a reaction in the chemical composition to deliver a metal coating to the surface of the component.
Electroless plating, as the name might suggest, removes electricity from the equation. Instead, the component is activated with an acid etch or a proprietary solution. This is a popular alternative plating process, particularly when it comes to coating a surface using nickel. Electroless nickel plating, sometimes shortened to simply EN plating, is used in a variety of industries, from deep-sea engineering to coating the tiny electrical components that make up computer motherboards.
There are a variety of different reasons electroless nickel plating has grown in popularity, but one crucial reason is its cost-efficiency. The process of electroplating is not a cheap one – it requires complex filtration equipment and electrical power. Electroless nickel plating, however, requires only chemical solutions.
The electroless nickel coating process delivers a smooth, uniform coating even when covering recesses, holes or jagged surfaces. This even coating is highly sought-after in many industries, where this method of plating nickel has seen a growth in popularity.
The most frequently used method of electroless nickel plating will create a nickel-phosphorus alloy coating. The automotive industry is the most common application for this type of coating, with valves, rotors and drive shafts being treated with nickel to increase their wear and corrosion resistance. For circuit board manufacturing, however, nickel is overlaid with gold, combining nickel and gold’s dual properties of corrosion resistance to create an extremely durable, long-lived component.
Nickel is also a popular choice for applications that require a high level of hardness, particularly in applications unsuited for other hard coatings, such as hard chrome. With heat treatment, electroless nickel coating’s hardness can be brought into a range comparable to hard chrome, in excess of 1000VHN. Because of this, it is sometimes used to salvage worn parts.
The use of electroless nickel plating has increased significantly in a variety of different industries across the globe, particularly the automotive manufacturing industry and industrial engineering. And with the multiple benefits it offers, including a cost-efficient plating process, high corrosion resistance and a level of hardness comparable to that of other hard-wearing coatings, it’s easy to see why.