Logam Aluminium

Aluminium is a chemical element with the atomic number 13 and symbol Al. It is a silvery-white, lightweight, and ductile metal that is widely used in various industries due to its excellent strength-to-weight ratio, low density, corrosion resistance, and good thermal and electrical conductivity.

Aluminium is abundantly available in the Earth's crust, making up about 8% of the crust by weight. It is obtained from bauxite, a reddish-brown ore primarily consisting of hydrated aluminium oxide (Al2O3·nH2O) and impurities such as iron oxides and silica.

The extraction of aluminium involves several steps, including mining, refining, smelting, and casting. The first step is to mine bauxite and extract alumina (Al2O3) from it through the Bayer process, which involves grinding the bauxite into a fine powder, dissolving it in hot caustic soda (NaOH), separating out impurities, and precipitating pure alumina using carbon dioxide (CO2).

The next step is to convert alumina into aluminium metal through the Hall-Heroult process, which involves electrolysis of molten alumina dissolved in cryolite (Na3AlF6) at high temperatures (around 960°C) and low pressures (around 1 atm). The process produces pure aluminium metal and oxygen gas (O2) at the cathode and anode respectively.

The resulting aluminium metal is then cast into various shapes and forms using different techniques such as rolling, extrusion, forging, and casting. These processes allow aluminium to be formed into a wide range of products, including sheets, plates, foils, wires, tubes, profiles, cans, cars, airplanes, buildings, and more.

Aluminium has numerous applications due to its unique properties. For example, it is used in the construction industry for framing, roofing, siding, and windows because of its strength, durability, and corrosion resistance. It is also used in the transportation industry for making car bodies, aircraft frames, and engine parts due to its lightweight and high strength-to-weight ratio. Moreover, it is used in the packaging industry for making beverage cans, foils, and containers as it is hygienic, easily formable, and recyclable. Other applications of aluminium include electrical conductors, heat exchangers, cookware, and more.

In summary, aluminium is a versatile metal that is widely used in many industries due to its unique properties such as strength, lightness, and corrosion resistance. Its extraction involves several steps, including mining, refining, smelting, and casting, which result in various forms and shapes suitable for different applications.