Hard chrome plating has been a preferred metal finishing solution since the 1940s — over time it has grown into a $20 billion industry. Chrome’s combination of superior hardness (which easily exceeds that of steel), excellent corrosion protection, abrasion resistance and bright, gleaming finish make chrome plating a top choice for various applications in industries such as automotive, aerospace, military, mining, machine tools, plastic molds and salvage.
However, chrome plating does have its disadvantages. The hexavalent chromium solution used in most hard chrome finishing processes exhibits poor throwing power, which makes it difficult to produce a uniform surface coating. Perhaps even more problematic are the health concerns.
Hexavalent chromium is a known human carcinogen and the U.S. Environmental Protection Agency has enacted stringent regulations on its use in manufacturing environments. Thus, companies that wish to implement hard chrome plating must go to great lengths and incur significant expenses to equip their facilities — which can make the process cost-prohibitive in many cases.
Nickel Offers a Solid Replacement Solution for Hard Chrome Plating
Many manufacturers and metal finishing companies are turning to nickel and nickel alloys as alternatives to chrome for their plating applications. Nickel’s ability to oxidize slowly offers the strong corrosion resistance required for various manufacturing applications. Nickel also adheres well to other metals, allowing it serve as either an undercoat or topcoat.
What’s more, bright nickel’s silvery-white, gold-tinged color can make it a viable replacement for chrome in processes where visual appeal is paramount.
Hard chrome alternatives featuring nickel include:
- Nickel Silicon Carbid: Nickel featuring a dispersion of hard silicon carbide particulates produces an electro-composite coating that provides excellent sliding wear resistance. Depending on the conditions and application, the coating can reduce the impact of wear up to 5-10 times greater than chromium. A nickel silicon carbide finish also provides exceptional corrosion resistance and adheres well to aluminum, titanium and other metals.
- Nickel-Tungsten Alloys: Nickel-tungsten serves as solid hard chrome substitute in high-temperature applications due its excellent resistance to decomposition when heated. Skilled metal finishing companies can produce nickel-tungsten alloys that will create a finish that is much harder than chrome and offers greater longevity. The NiW plating process is also more efficient than chromium plating — it’s possible to plate multiple layers in a single step, which saves time and money.
- Electroless Nickel: EN can provide a good barrier coating that enhances corrosion resistance. Because electroless nickel does not require an electrical current for deposition, the process results in a more uniform coating application than hard chrome plating. Applications where EN can serve as an acceptable substitute for chrome include plastic and glass molds, gears, bearings, medical devices and aircraft parts and components.
*Please note that Sharretts Plating does not plate with chrome. This content is for educational purposes only.
Contact SPC to learn more about hard chrome plating alternatives and receive a free metal finishing project quote today.
