Nickel was used as coinage in nickel-copper alloys for several thousand years, but was not recognized as an elemental substance until 1751 when the Swedish chemist Baron Axel Frederic Cronstedt isolated the metal from niccolite ore.Nickel is a hard, malleable, ductile metal, capable of taking a high polish. Metallic nickel is not very active chemically. It is soluble in dilute nitric acid and becomes passive in concentrated nitric acid. Nickel is used chiefly in the form of alloys. It imparts great strength and corrosion resistance to steel. Nickel steel, containing about 2 to 4 percent nickel, is used in automobile parts such as axles, crankshafts, gears, valves, and rods; in machine parts; and in armor plate. Some of the most important nickel-containing alloys are German silver, Invar, Monel metal, Nichrome, and Permalloy.

Nickel is also used to strengthen alloys such as copper and iron. With copper and nickel, brass is formed. Its chemical characteristics give the reason for its strength. Nickel is used as a protective and ornamental coating for metals, particularly iron and steel, that are susceptible to corrosion. The nickel plate is deposited by electrolysis in a nickel solution.Nickel ores usually contain impurities, chief among which is copper. Sulfide ores, such as pentlandite and nickeliferouspyrrhotite, are usually smelted in a blast furnace and shipped in the form of a matte of copper and nickel sulfide to refineries, where the nickel is removed by various processes.The United States has no large deposits of nickel and accounts for less than 1 percent of the annual world output. Most of the nickel that is used in the United States must be imported; about 30 percent of annual U.S. consumption is recycled.

Posted 2011-01-29 and updated on Jun 08, 2011 4:08am by crisd

 Jun 08, 2011 4:08amThis has made my day. I wish all postngis were this good. by Veanna
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