Aluminum Essay Research Paper AluminumAluminum is a

Aluminum Essay, Research Paper

Aluminum

Aluminum is a lightweight, silver-colored metal that can be formed into almost any shape. It can be rolled into thick plates for armored tanks or into thin foil for chewing gum wrappers. It may be drawn into wire or made into cans. Aluminum does not rust, and it resists wear from weather and chemicals. Aluminum is called aluminium in English-speaking countries outside the United States. Its atomic number is 13 and its atomic weight is 26.9815.

Pure aluminum, known as Al on the periodic scale, is soft and has little strength. For this reason, aluminum producers almost always blend it with small amounts of copper, magnesium, zinc, and other elements to form aluminum alloys. The added elements give aluminum strength and other properties that make it one of the most useful of all metals. In fact, the world uses more aluminum than any other metal except iron and steel.

The largest share of aluminum alloy production goes to the construction industry for use in such items as window frames, gutters, and the roofs and sides of buildings. Manufacturers of transportation equipment use huge amounts of aluminum in airplanes, automobiles, boats, railroad cars, and trucks. The packaging industry makes beverage cans, bottle caps, foil pouches, frozen food trays, and other items of aluminum. Aluminum is used in much electrical equipment, including light bulbs, power lines, and telephone wires. Thousands of other products also contain aluminum. These products include air conditioners, cookware, golf clubs, knitting needles, lawn furniture, license plates, paints, refrigerators, rocket fuel, toasters, and zippers.

Aluminum is the most plentiful metallic element in the earth.s crust and the third most common of all the elements, after oxygen and silicon. Aluminum makes up about eight percent of the earth.s crust. But unlike some other metals, such as gold and silver, aluminum never occurs free in nature. It is always chemically combined with other elements. People had no way of separating aluminum from these elements until the 1800.s. Scientists then developed processes for separating the elements and producing aluminum. These processes have been used to make aluminum ever since.

Only a small percentage of aluminum is used in pure form. It is made into such items as electrical conductors, jewelry, and decorative trim for appliances and cars.

Almost all aluminum is produced in alloy form with up to 15 percent of one or more other elements. The chief elements are copper, magnesium, manganese, silicon, tin, and zinc. Copper and magnesium increase the strength and hardness of aluminum. Magnesium also makes aluminum easier to weld. Manganese helps aluminum resist rust and also provides strength. Silicon lowers the melting point of aluminum and makes it easier to cast. Tin makes aluminum easier to shape with metalworking tools. Zinc, especially when combined with magnesium, gives added strength. Other elements may also be alloyed with aluminum for special purposes. These elements include bismuth, boron, cadmium, chromium, cobalt, iron, lead, lithium, nickel, sodium, titanium, vanadium, and zirconium.

Aluminum, with its alloys, has many valuable properties that make it an exceptionally useful metal. These properties include light weight, strength, corrosion resistance, electricity conduction, heat conduction, and light and heat reflection.

Aluminum is one of the lightest metals. It weighs about 170 pounds per cubic foot – about a third as much as steel. As a result, aluminum has replaced steel for many uses. For example, some parts of automobiles and trucks are now made of aluminum rather than steel because lighter vehicles use less fuel. Products packed in aluminum containers cost less to ship because the containers weigh less than those made of other metals.

Although pure aluminum is weak, certain aluminum alloys are as strong as steel. Such alloys are used in the bodies of airplanes and trucks, in guardrails along highways, and in other products that require great strength. Aluminum alloys lose some strength at high temperatures, but unlike many other metals, they get stronger at extremely low temperatures. Aluminum alloys are widely used in equipment for processing, transporting, and storing liquefied natural gas, which has a temperature of .260 degrees Fahrenheit.

Some metals corrode if they are exposed to oxygen, water, or various chemicals. A chemical reaction occurs that causes the metals to rust or become discolored. When aluminum reacts with oxygen, however, the metal forms an invisible layer of a chemical compound called aluminum oxide. This layer protects aluminum from corrosion by oxygen, water, and many chemicals. It makes aluminum especially valuable for use outdoors, where the metal resists the effects of wind, rain, and pollution.

Aluminum and copper are the only common metals suitable for use as electrical conductors. Aluminum conducts electricity about 62 percent as well as copper, but aluminum weighs about a third as much. Aluminum wire can therefore carry the same amount of electric power as copper wire that weighs twice as much. In addition, aluminum is more ductile than copper, which means it can more easily be drawn into wires. Aluminum wire is used for nearly all high-voltage lines in the United States.

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