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Technology and its processes today are very widespread and constantly making it easier to solve our national problems. Recently, technology has become the popular topic in the aspect of solving national environmental and efficiency problems. Throughout the nations people seem to be worrying more about controlling our waste bi- products that have the potential to become widespread hazardous problems. The Airline industries have taken matters into their own hands and have begun to fund new research and development projects to help out with the growing concern of environmental and efficiency problems. As a result of these new research and development projects, airline industries have become more efficient due finding new ways to make their big metal planes more lighter, stronger, efficient, and even more cost effective. The first question you may ask yourself is how these airline industries are making their planes lighter, but at the same time, more stronger. The answer to this question lies in the process of making alloys. An alloy is a solid mixture of two or more elements, at least one of which is a metal. Alloying a metal with a nonmetal or another metal does not really alter the metals physical properties, but it alters the engineering properties like the tensile strength, shear strength, hardness, appearance and dimensional properties and weight. The primary alloy used in the aircraft industry is duralumin. Duralumin is comprised of aluminum, copper, magnesium, and manganese1. To make duralumin, pure aluminum is needed. Pure aluminum comes from aluminum compounds like aluminum oxide found in clay. The problem with clay is that there are a lot of other elements in the clay that are not useful for the production of pure aluminum. This obstacle is overcome by mining bauxite ore which relatively easy to obtain through open pit mines and contains 45-60% aluminum oxide. Manufacturing pure aluminum is separated into two phases, the first phase (Bayer Process) which is obtaining the bauxite ore by mining it, and then the second phase, (Hall-Heroult process) which is the process of mixing the purified aluminum oxide with cryolite (a solid made of sodium fluoride and aluminum fluoride) and then heated to about 980o Celsius. The molten mixture is then electrolyzed to reduce the aluminum ions to form aluminum metal. Once pure aluminum is produced you can make it into an alloy by melting it again and mixing any other element in it and then letting it cool down to a solid state.
 * || Figure 1: The Bayer process on industrial scale ||
 * || Figure 2: The Hall Heroult Process ||



Aluminum alloys are widely used in the aircraft industries because of their chemical and physical properties. For its physical properties, the aluminum alloys are very hard to melt, pure aluminum melts at 660o Celsius and has a boiling point of 2,450o Celsius2. It is both ductile and malleable and is a excellent conductor of electricity which is why alu[]minum is used in a lot of electrical equipment. It has a density of 2.7g which makes it very light compared to iron. The chemical properties of aluminum are in its own way, interesting. When in moist air aluminum reacts with oxygen to form aluminum oxide which forms a very thin layer on the surface of the aluminum. This coating acts as a shield and prevents the pure aluminum metal from further reacting with oxygen. This means that aluminum will not rust because it has a resistance to oxidation.3 With these properties aluminum is an excellent candidate for aircraft structures because it is relatively light compared to iron. Aluminum also has the property of resistance to oxidation, which means that planes can fly in rain and be left outside without having to worry about corrosion. Also aluminum is not magnetic which means it can easily be separated from other metals which will aid in its recycling process. Since technology keeps on solving problems and making more fuel efficient, more powerful, and faster airplanes companies sometimes have to get rid of old planes that are no longer cost effective to up keep and keep running. These planes usually go to a plane bone yard where they are stripped down of their valuable materials to get ready for the recycling process. Since aluminum is very expensive to make, taking two metric tons of aluminum oxide and 17,000 kilowatt hours (kWh) of electricity to produce 1 ton of aluminum4, and produces considerable waste products it is easier to keep aluminum and its alloys intact. They do not rust so aluminum and its alloys can be left outside without having to worry about corrosion and since they have the property of not being magnetic they can be separated by a big industrial magnet from the rest of the scrap metals. Technology sometimes leaves us in the dust with old things that are not cost effective to use. The good thing about old planes though, that the airline industries have found out, is that they can be scraped and recycled into brand new cost effective planes. Aluminum will not rust because it has the cool chemical property of oxidation resistance and therefore it will not weaken in structure over the years. Also aluminum is easy to separate from scrap piles because it’s not magnetic.
 * || Figure 3: An airplane bone yard located in Tucson, Az. ||
 * || Figure: 4 441 ||

Sources:


 * 1) "Duralumin (alloy) -- Britannica Online Encyclopedia." //Encyclopedia - Britannica Online Encyclopedia//. Web. 20 Nov. 2009. .


 * 1) "Aluminum - General Properties, Where Aluminum Comes From, How Aluminum Is Obtained, Uses, Chemistry And Compounds." //Science Encyclopedia//. Web. 20 Nov. 2009. .


 * 1) Hill, John W., and Doris K. Kolb. //Chemistry for Changing Times//. 11th ed. Upper Saddle River, NJ 07458: Pearson Education Inc., 2007, 2004, 2001, 1998. Print.


 * 1) "Aluminum, Chemical Element - Overview, Discovery and naming, Physical properties, Chemical properties, Occurrence in nature, Isotopes." //Chemistry: Foundations and Applications//. Web. 20 Nov. 2009. 

Figures:


 * 1) "Aluminium Extraction." //Sam Davyson//. Web. 20 Nov. 2009. .


 * 1) "Aluminium Extraction." //Sam Davyson//. Web. 20 Nov. 2009. .


 * 1) "The Boneyard: Where Military Aircraft Go to Die." //Neatorama//. Web. 20 Nov. 2009. .


 * 1) "Summary Report of Energy Use in the Canadian Manufacturing Sector, 1995-2005." //Office of Energy Efficiency | L'Office de l'efficacit//. Web. 20 Nov. 2009. .