Chrome plating is a metal coating process for depositing a thin layer of chromium on a material’s surface. Chrome plating uses an electroplating technique to produce chromium coatings as thin as 0.001 inches (0.025 mm).
Chrome plating can be used to provide a variety of chromium alloy coatings for corrosion and wear resistance with a variety of deposition thicknesses.
Chrome plating is divided into two types:
Chrome plating for decoration. A coating of nickel and a layer of chromium is used in this type. Nickel provides the object’s surface with a gleaming, polished appearance. A chromium layer is put on top of the nickel layer after it has been deposited. The chromium coating increases the material’s corrosion resistance while also improving scratch and wear resistance. The entire thickness of decorative chrome plating is usually less than 0.001 inches.
Plating in hard chrome. This style is commonly employed in industrial situations where aesthetics aren’t a priority. While hard chrome plating can improve the corrosion resistance of the material it is applied to, it is mainly employed to boost the wear resistance of particular components. Hard chrome plating is a thicker version of decorative chrome plating that is widely applied to various types of steel.
Since the 1940s, hard chrome plating has been the standard metal finishing method, and it has evolved into a $20 billion business. Chrome plating is a popular choice for a variety of applications in industries such as automotive, aerospace, military, mining, machine tools, plastic moulds, and salvage due to its superior hardness (which easily exceeds that of steel), excellent corrosion protection, abrasion resistance, and bright, gleaming finish.
Chrome plating, on the other hand, has several drawbacks. The hexavalent chromium solution utilised in most hard chrome finishing methods has low throwing force, making homogeneous surface coating challenging to achieve. The health issues are perhaps even more problematic.
Hexavalent chromium is a proven human carcinogen, and the United States has banned its use. In addition, the Environmental Protection Agency has implemented strict guidelines for its use in manufacturing settings. As a result, companies that want to use hard chrome plating must go to considerable lengths and spend a lot of money to equip their facilities, making the procedure prohibitively expensive in many circumstances.
FOR HARD CHROME PLATING, NICKEL PROVIDES A SOLID REPLACEMENT SOLUTION
Several manufacturers and metal finishing businesses are turning to nickel and nickel alloys as alternatives to chrome for plating applications. Nickel’s slow oxidation provides the corrosion resistance needed in a variety of manufacturing applications. In addition, nickel binds readily to other metals. Therefore it can be used as an undercoat or a topcoat.
Furthermore, bright nickel’s silvery-white, gold-tinged appearance makes it a potential replacement for chrome in operations where aesthetics are essential.
Alternatives to hard chrome with nickel include:
Nickel Silicon Carbid: A nickel electro-composite coating with hard silicon carbide particles dispersion gives exceptional sliding wear resistance. The coating can reduce the impact of wear up to 5-10 times more than chromium, depending on the conditions and application. In addition, a nickel silicon carbide finish has excellent corrosion resistance and adheres well to metals such as aluminium, titanium, and other metals.
Nickel-Tungsten Alloys: Due to its strong resistance to breakdown when heated, nickel-tungsten serves as a solid hard chrome alternative in high-temperature applications. Skilled metal finishing businesses can manufacture nickel-tungsten alloys that are significantly tougher than chrome and last longer. NiW plating is also more efficient than chromium plating because it allows numerous layers to be plated in a single operation, saving time and money.
EN (Electroless Nickel) is a good barrier coating that improves corrosion resistance. In addition, electroless nickel plating produces a more uniform coating application than hard chrome plating since deposition does not require an electrical current. Plastic and glass moulds, gears, bearings, medical equipment, and aviation parts and components are among the applications where EN can be used as a chrome alternative.