Aluminium is a white shiny metal with the atomic number 13 and chemical symbol Al. It is a very strong and light metal which is used for industrial purposes due to its properties that help it to perform under extreme conditions.
It is a chemically stable compound that can be formed into several crystalline phases. It reverts to the most stable hexagonal alpha phase at elevated temperatures, which makes it the most desirable material for structural applications.
The main use of aluminium oxide is as an electrical insulator. It is used as a substrate for integrated circuits but also as an insulator for superconducting devices such as single-electron transistors and SQUIDs.
It has good thermal conductivity and is refractory in a wide range of environments. It is used for lining high-temperature appliances such as kilns, furnaces, incinerators and reactors.
Alumina is an abrasive mineral that forms in the crystalline form of corundum, a 9 on the Mohs scale of hardness (just below diamond). It is used as an abrasive in emery boards, sandpaper and grinding and polishing wheels and belts, lens grinding devices and gem polishing wheels.
It is also used as a ceramic for use in adsorbents and catalysts. It is widely utilised in the aerospace industry and in the production of many commercially important chemicals.