Producing precision mechanical parts involves several steps and treatments, including nickel plating and chrome plating. But which is better? Nickel plating and chrome plating change the surface properties of metals in different ways. Nickel plating changes hardness and resistance to external agents, making the surface more corrosion-resistant. Chrome plating, on the other hand, coats the surface with a layer of chromium for functional and/or aesthetic reasons.
Differences between nickel plating and chrome plating
The choice between nickel and chrome plating depends on the properties you want to give the mechanical parts. This is only possible with sector knowledge, experience and a team of professionals. But first: what is nickel plating?
Nickel plating is divided into electroless (chemical) and electrolytic, depending on how the nickel is deposited. The first deposits nickel on various materials using a chemical reducing agent in the treatment solution, while the second uses electric current to deposit nickel on metal surfaces only. The chemical process has the advantage of versatility (metal, plastic and glass) and can be applied even to complex shapes, while electrolytic nickel plating provides an excellent level of corrosion resistance (varying with the metal and layer thickness).
And what is chrome plating for? It can serve different purposes: hard chrome plating and decorative chrome plating. Hard chrome plating deposits a layer of chromium of varying thickness on the surface to increase its hardness and make it more resistant to wear and corrosion. Decorative chrome plating gives a very distinctive shiny, bright appearance. It is used for decorative, never functional, purposes.
How to choose between nickel and chrome plating
Experts in precision parts use nickel or chrome plating after weighing the pros and cons according to the required final properties and end use.
Hard chrome plating offers high hardness, considerable wear resistance, reasonable corrosion resistance, a variable thickness that can exceed 100 µm and low cost. However, it is uneven on thick layers and limited in some industries. Decorative chrome plating, although ornamental and cheap, cannot be used to improve the mechanical functions of materials. Electroless nickel plating (specific to metals) is used when a uniform thickness, excellent corrosion resistance and high wear resistance are required. On the other hand, a heat treatment must be managed to achieve maximum hardness.