The chromium plating is usually applied over bright nickel plating. Hydrogen is often introduced during manufacture from operations such as forming, coating, plating or cleaning. Usually no plating or other coating is involved. Copper pennies are useful in demonstrating the concept of copper plating. Corrosion-resistance can be increased by cadmium plating or phosphating. Various finishing and buffing processes are used in preparing components for decorative chrome plating. New materials arrived, including chrome plating, stainless steel, and plastic. Electrical resistance is higher compared to pure metal plating. This gives a high-luster finish similar in appearance to nickel plating. The striking method is also used in combination with the plating of different metals. Inside this area is a circle exposing the copper plating beneath. This is one area where titanium is used extensively as armour plating. There are many factors to consider in selection of either electrolytic or electroless plating methods. Vanadium alloys are used in springs, tools, jet engines, armor plating, and nuclear reactors. Width over outer surface of the shell plating&colon; .