Electroless nickel plating is a process that is ideal for applications where a component must be resistant to issues like chipping and corrosion, must have high lubricity, and generally needs to be able to withstand even the harshest environments. It is also known for a uniform, consistent plate thickness when compared to alternative methods.
But what many don't realize is that in addition to being reliably uniform, this type of plating thickness is also highly customizable.
While the thickness of electroless nickel plating will coincide with your application and specification, the typical thickness is between 12 and 25 microns. However, in theory, one could continue to build the thickness to any specification required given enough time and resources. This is quite a unique property of the chemical reactions in the electroless process, and it's made more beneficial by the fact that electroless nickel plating results in a highly uniform finish at any thickness.
Much of this has to do with the mechanics of the process itself. After a thorough cleaning, the component in question is placed carefully into a chemical bath with nickel phosphorous compounds. This, coupled with a reducing agent, cause metal ions to be deposited evenly onto the surface. The process is centered around an autocatalytic chemical reaction as opposed to the use of an electrical current, meaning that the resulting coating is reliable, repeatable, and of uniform thickness.
This is essential because things like cracks, crevices, seams, and even inherently complicated geometries are not an issue for electroless nickel plating where they would be for other techniques.
Electroless nickel plating helps to avoid issues that are inherent in other techniques, such as "the dog boning effect” seen in traditional electroplating. Dog boning is an inconsistent deposit where points, corners, or sharp edges on a component may build up plating that’s thicker than on the flatter surface areas. This is due to the uneven way that electric currents are focused in the electroplating process.
On mission-critical parts like those used for aviation and aerospace, this inconsistency must be avoided at all costs. Dog boning can be amplified when too strong of an electrical charge is applied to the material per square foot during electrolytic plating. This effect is also more pronounced as the thickness of the plate increases.
Pitting is another example of a common problem that limits the practicality of plating a component past a certain thickness — but is not seen in electroless nickel plating.
Finally, it should be noted that the superior thickness options of electroless nickel plating can also mean longer dwell times than some alternative methods. The chemical process will slowly build up nickel deposits on the surface of the component, at an unchangeable speed, while it’s submerged in a bath with nickel ions. While the finished results are superior to other options like zinc in many ways, a careful selection must still be made for applications where time is a factor.
If you're interested in learning more about why electroless nickel plating thickness is so customizable, or if you're eager to get your next big project started right away, please contact us today. You can also click here to request a free quote and we'll get everything you need back to you in 24 hours or less.