Bayer's process is still the standard means of production for most of the industrial aluminum today. It is a complicated process involving mining, extracting, smelting, and casting.
The discovery of Bauxite made aluminum cost effective for mass production. Bauxite is a rock that was first discovered in 19th-century France. It is widely available and it is the primary ore from which aluminum is produced.
Though there are some deposits in Europe, most of today's bauxite comes from sub-tropical or tropical areas like:
Africa,West Indies,South America,Australia
Most of the expense in the production of aluminum is incurred during the extraction process. The first step in the process is to purify the bauxite into aluminum oxide, which is a white powder from which aluminum can be extracted.
The aluminum oxide must be made into the molten form so that electricity can pass through it in the next step of the process. To achieve this, it is dissolved into another compound that has a lower melting point. Once the aluminum compound is ready, electrolysis is used to extract useful aluminium metal. Further processing through smelting purifies the aluminum to around 99.97%. The aluminum oxide is almost always combined with other metals to form alloys with different properties and applications. One of the most frequently used is 6061 Aluminum, which contains magnesium and silicon. It is a general purpose metal that is wieldable, heat treatable and may be cold worked or annealed. 6061 Aluminum is used to make truck and marine components and pipelines. 7075 aluminum is very strong and corrosion resistant and alloyed with zinc. It has good fatigue strength, but because of this it is not wieldable. This aluminum alloy is not common, and therefore costs more than others. It is used mainly in aircraft construction, bicycle construction and to manufacture sports equipment for rock climbers and lacrosse players. Aluminum 1100 is a very soft alloy, and it is one of the most pure alloys. It has low strength and is therefore very wieldable and formable. It cannot be hardened by heat treatment and is used to make chemical equipment and railroad tank cars.
After extraction, the aluminum can be 'cast' in a process very similar to the process of casting iron. Aluminum casting is the method in which it is made into various shapes for its intended function, otherwise known as its aluminum profile.
It can also be extruded. Aluminum extrusion is a shaping method in which aluminum is forced into a specific shape by forcing it to flow through a shaped opening in a die.Aluminum can be made into virtually any shape. Aluminum suppliers can use rolling to produce aluminum coils, plates, strips and sheets. During the rolling process, the aluminum becomes less brittle and more ductile. Rolling is also capable of creating very thin products. Roll forming can also produce hollow products like aluminum tubing and pipes by using specially shaped rollers. Stamp pressing, a process where flat aluminum sheets are shaped into parts by a die cavity and enormous amounts of pressure, is also used to form some aluminum shapes. In the extrusion method, aluminum billets are heated and pushed through a metal die under great pressure to create shapes such as bars and rods. Further fabrication of the aluminum supply can be done upon completion, such as cutting to length, drilling and machining. Forgings are created by hammering, pounding or squeezing the aluminum into parts. Casting involves two methods. One is sand casting, in which a temporary sand mold is created to make a part. The other is die casting, where the mold is permanent and is usually cast iron or steel. This is the most widely used method of aluminum forming, and it involves pouring molten aluminum directly into the mold. Aluminum supply can also be bent, made into a powder, joined by welding or milled, depending on the desired product. Aluminum plates and aluminum coils are used mostly for industrial applications. While other shapes are needed for household appliances and utensils. It also lends itself well to powder coating which gives it a tough, and decorative finish.
Having a knowledge of how aluminum is very important, but it is more important to find a quality supplier that will provide a great product and great service.