ENP: Electroless Nickel Plating Process
Electroless nickel plating is fueled by an auto-catalytic chemical reaction to deposit a nickel-alloy coating onto conductive and non-conductive components.
While most plating processes are catalysed by an electrical current, electroless nickel plating uses an auto-catalytic reaction. No current is required, so the substrate does not need to conduct electricity to be plated. Because of this, our ENP service can coat aluminium, stainless steel, mild steel, brass or copper in a hard, non-corrosive, conductive layer.
The component is prepared and then submerged in an aqueous solution of Nickel salt and Hypophosphite salt (a reducing agent that contains phosphorus). The solution also contains complexant, neutraliser, buffer, stabiliser and brighteners.
Maintained at a constant temperature and acidity, the chemical reaction breaks down the nickel and phosphate salts into ions, which then combine into a nickel-phosphate alloy and adhere firmly to the substrate at an average rate of up to 20 microns per hour.
There are three types of electroless nickel plating, categorised by low, medium and high phosphorus content.
We provide the most popular type: Medium Phosphorus Electroless Nickel Plating, resulting in a 7-9% phosphorus content in the nickel-alloy coating.
The more phosphorus present in the nickel alloy, the greater the component’s corrosion resistance will be. However, higher phosphorus content also decreases the hardness of the coating. Medium phosphorus electroless nickel coating strikes a balance that satisfies most applications.
Electrolytic nickel plating uses a cathode and an anode to electrolyse the solution and begin the process. This means it can only be used on conductive materials, such as steel, copper and brass. Electrolytic plating also does not always offer a uniform finish, requiring wider tolerances.
Electroless nickel plating provides a completely uniform finish in all crevices and exposed surfaces, no matter how complex the component’s configurations.
ENP can also be used to improve the surface of a component, to provide a regular surface for desired finishes, or to add a conductive coating to a non-conductive part.
Medium Phosphorus Electroless Nickel Plating has many advantages over other electroplating methods.
ENP provides a uniform coating, with no deviation in plating thickness across the entire surface, regardless of shape.
The nickel-phosphorus alloy coating has excellent corrosion resistance, perfect for marine use and in oil and gas systems.
Nickel alloy has good hardness and wear-resistance can be further hardened with heat treatment processes post-plating.
Because electroless nickel plating provides a completely uniform coating, it imparts a low friction coefficient to the component. This is fantastic for automotive and manufacturing components.
Electroless Nickel plating can plate to tight manufacturing tolerances, because we can accurately measure the thickness of nickel being plated onto a component. We regularly check the thickness during plating using our XRF machine, and analyse our plating solution’s additions, pH and temperature to estimate the appropriate timings. When the desired thickness is reached, we stop plating.
Suitable Substrates for ENP include: aluminium alloys, copper, plastic, steel, stainless steel and even glass.
Our plating team has built up experience over the past 30+ years, continually learning the newest methods to provide quality nickel plating services to clients large and small.
Based in the Midlands, we can serve the whole of the UK, with quick turnaround times to keep manufacturing projects moving.
All Electroless Nickel Plating jobs undergo rigorous testing to high-quality standards during in-house quality checks. Our clients benefit from a strong relationship with a reliable plating supplier with easy customer service.
Electroless Nickel plating is suitable for many industries. Our medium phosphate nickel plating is among the most popular, balancing hardness with corrosion resistance. Industries we serve:
Component types coated using ENP:
Check here for answers to common questions about medium phosphorus EN plating services.
Electroless Nickel plating is extremely durable, favoured for its wear-resistance and corrosion-resistance. The lifespan of electroless plated items depends on their application and the environment, but components coated by this method can retain the coating for more than 15 years.
The cost depends on the size and quantity of components to coat, as larger items will require greater quantities of all chemicals involved. For an accurate quote, please contact our team today.
The best plating service depends on the application and the material of the components. Both hard chrome and EN plating have excellent abrasion resistance
Zinc plating is best reserved for thin components and plate wire. It is affordable but has a poor appearance and is only applicable to steel.
Hard Chrome plating can be used for steel, copper and brass, but electroless nickel plating can coat components made from steel, stainless steel, copper, aluminium alloy, glass and plastic.
Customers can specify their desired plating thickness with electroless nickel plating, whereas hard chrome is always between 10-30 microns.
Electroless nickel plating has the advantage of being able to plate to tight manufacturing tolerances, because we can accurately measure the thickness of nickel being plated onto a component.
We regularly check the thickness during plating using our XRF machine, and analyse our plating solution’s additions, pH and temperature to estimate the appropriate timings. When the desired thickness is reached, we stop plating.
We can achieve coating as thin as 3 microns or as thick as 75 microns.
Electroless Nickel Plating
If you have any questions regarding our services, please contact us by calling 0121 556 3636 or email us at [email protected].
