Thermite

Thermite reacting made with iron oxide and aluminum powder

Thermite is a mixture of a metal powder and an oxide. The most common mixture is aluminum powder and iron oxide (rust). Thermites have diverse compositions. Fuels include aluminium, magnesium, titanium, zinc, silicon, and boron. Aluminium is common because of its high boiling point and low cost. When ignited, the mixture heats to an extremely high temperature and the metals violently react. In iron oxide and aluminum thermite, aluminium forms stronger and more stable bonds with oxygen than iron. This results in a Fe2O3 + 2 Al → 2 Fe + Al2O3 reaction (pure iron and aluminum oxide). If copper oxide is used, the mixture explodes instead. Applications include welding, incendiary devices, and joining railway tracks. It also has potential for misuse.