Nickel is a metallic chemical element similar in form to chromium, aluminum and titanium, but is slow to react in air at normal temperatures and pressures. Nickel is magnetic and is valuable for the alloys it forms, especially many superalloys, and particularly stainless steel.
Thirty-eight percent of annual nickel use is in nonferrous alloys (or mixed with metals other than steel) and superalloys (metal mixtures designed to withstand extremely high temperatures and/or pressures, or to have high electrical conductivity). Nickel is used as a coating on other metals to slow down corrosion. Nickel coatings account for 14% of nickel use.
The remaining 6% of the annual nickel use is for a variety of purposes including the production of coins, nickel-cadmium and nickel-metal hydride batteries; as a catalyst for certain chemical reactions; and, as a colorant, nickel is added to glass to give it a green color. The U.S. 5-cent piece is called a "nickel" because it only contains 25% nickel.
