①Density. The density of aluminum is very small, only 2.7g/cm. Although it is relatively soft, it can be made into various aluminum alloys, such as hard aluminum, super hard aluminum, rust-proof aluminum, cast aluminum, etc. These aluminum alloys are widely used in manufacturing industries such as aircraft, automobiles, trains, and ships.
②Thermal conductivity. Aluminum is a good conductor of heat. Its thermal conductivity is three times greater than that of iron. Aluminum can be used in industry to manufacture various heat exchangers, heat dissipation materials, cookware, etc.
③Extensibility. It has good ductility (its ductility is second only to gold and silver), and can be made into aluminum foil thinner than 0.01mm at 100℃~150℃. These aluminum foils are widely used to package cigarettes, candies, etc., and can also be made into aluminum wires, aluminum strips, and can be rolled into various aluminum products.
④Electrical conductivity. Second only to silver and copper, although its conductivity is only 2/3 of copper, its density is only 1/3 of copper. Therefore, to transport the same amount of electricity, the quality of aluminum wire is only half that of copper wire. The oxide film on the surface of aluminum not only has corrosion resistance, but also has certain insulation properties, so aluminum is widely used in the electrical appliance manufacturing industry, wire and cable industry, and radio industry.