Electroless nickel plating is primarily used because of its excellent corrosion protection. The electroless process deposits a uniform coating, regardless of the shape of the part, unlike electroplating that relies on current density. Electroless nickel coatings have good wear resistance because of the high hardness and natural lubricity. Relatively soft substrates with poor abrasion resistance, such as aluminum, can be given a hard, wear-resistant surface with electroless nickel.
Electroless nickel plating is applied evenly over all geometries and is an excellent coating, providing corrosion protection and friction reduction. When used for repair, it can be plated to size with out re- machining in many circumstances. This is useful if the thickness required is less than .002” per side. The illustration shows the difference between electroplating and electroless plating. Electroless nickel is also useful to plate down inside tubes and deep bores where hard chrome cannot.
Electroless Nickel Plating
Medium Phosphorus – Most widely used electroless nickel bath. Porosity is low, and conversely corrosion resistance is higher than low phosphorus. Better wear resistance and hardness compared to high phosphorus. Excellent for molds and dies as well as chemical handling equipment.
High Phosphorus – Dense and dull in comparison to medium and low deposits. Provides the best corrosion resistance, but is not as hard as the lower phosphorus content.
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Electroless Nickel Deposit properties, specifications and applications Electrolessnickelplating.com