The Basic Physical Data
| Property | Value |
|---|---|
| Melting point | 660 °C (1,220 °F) |
| Boiling point | About 2,327 °C (4,221 °F); some modern references cite 2,470–2,519 °C |
| Relative density | 2.70 g/cm³ (about one-third of steel) |
| Abundance | Third most abundant element in the Earth's crust (after oxygen and silicon); the most abundant metal |
What Is Aluminum?
Aluminum is a silvery-white light metal with good ductility, supplied in rod, flake, foil, powder, ribbon and wire forms. In moist air it forms a thin oxide film that prevents further metal corrosion. Aluminum powder burns violently in air with heat, emitting a blinding white flame. Chemically it dissolves in dilute sulfuric, nitric and hydrochloric acid and in sodium and potassium hydroxide solutions, and is insoluble in water.
Why the Melting and Boiling Points Matter
Low melting point (660 °C): aluminum melts at a much lower temperature than steel (about 1,370–1,530 °C), which makes casting, die casting and recycling energy-efficient - a key reason aluminum recycling consumes only about 5% of the energy of primary production.
High boiling point: the wide liquid range simplifies casting control; evaporation is only a concern in vacuum or high-temperature processes.
Low density: at 2.70 g/cm³, aluminum is about one-third the weight of steel, the basis of its use in transportation.
Main Uses
The development of the aviation, construction and automobile industries requires material characteristics that the unique properties of aluminum and its alloys provide, which greatly promotes the production and application of this metal:
Aviation: aircraft skins, frames and structural parts (2xxx/7xxx alloys).
Construction: curtain walls, windows, roofing and structural members (6xxx alloys).
Automobile: body panels, wheels, heat exchangers and lightweight structural parts (5xxx/6xxx alloys).
Packaging: aluminum foil and cans (1xxx/3xxx/8xxx alloys).
Electrical: conductors, busbars and transformer windings (1xxx alloys).
