Electroplated cadmium is a robust and versatile metallic coating. Cadmium is a soft white metal that, when plated onto steel, cast iron, malleable iron, copper, and powdered metal, functions as a “sacrificial coating,” corroding before the substrate material. To enhance the corrosion protection of cadmium plating, chromate conversion coatings can be applied over the plated metal, yielding the familiar gold color as seen in the above picture. Other colors, such as olive drab are also available.
Chrome plating is a metal coating method used to create a thin layer of chromium on the surface of a material. Chrome plating uses a technology known as electroplating to create chromium layers that can be less than 0.001 inch (0.025 mm).
Chrome plating can be used to make different chromium alloy coatings with a variety of deposition thicknesses for corrosion and wear resistance.
Modeling Corrosion and Corrosion Protection
Corrosionpedia explains Chrome Plating
There are two main types of chrome plating:
Decorative chrome plating. This type employs a layer of nickel and a layer of chromium. The nickel gives the surface of the object its shine and its polished look. Once the nickel layer has been deposited, a chromium layer is added on top of it. The chromium layer helps increase the corrosion resistance of the material and also improve the resistance to scratching and wear. Decorative chrome plating usually has a total thickness under 0.001 inch.
Hard chrome plating. This type is typically used in industrial settings where aesthetic appeal is not the primary concern. Hard chrome plating, while it can improve the corrosion resistance of the material to which it is applied, is primarily used to increase the wear resistance of certain components. Hard chrome plating is commonly applied to various types of steel and is almost always thicker than decorative chrome plating.