Aluminum powder is used in the production of many types of explosives and fireworks. It is also employed in the manufacturing of certain types of electronics. Powdered aluminum is included in many paints and sealants. Certain products designed to carry electrical current, such as solar cells, are also often made using aluminum powder.
The most spectacular uses of aluminum powder take advantage of its ability to produce spectacularly exothermic oxidation-reduction reactions. Aluminum can be mixed with a metal oxide, and the resulting powder will burn brilliantly and release a tremendous amount of energy in a very short period of time. This chemical reaction has been used to produce flash powder, in which aluminum and potassium perchlorate react vigorously together to produce a bang and a flash. Iron oxide powder and aluminum powder, when mixed, form thermite, which produces a great deal of light and a tremendous amount of heat, which is useful in many industrial processes.
Fireworks and explosives commonly take advantage of the properties of aluminum powder. Explosives manufactured with aluminum are easier to handle safely than are many other varieties. Fireworks based on aluminum powder make use of its highly energetic but predictable behavior by mixing aluminum compounds with other chemicals to produce spectacular and varied effects.
Rocket fuel is often made with aluminum, and many solid rocket fuels are based on chemical reactions involving this metal. In fact, this type of fuel was used to power the solid rocket boosters for the space shuttle. Aluminum powder can also as an additive to liquid rocket fuels.
Aluminum powder can be used in metallurgy as well. Some alloys are created using aluminum, typically by the addition of powder to a molten metal. In some cases, powdered aluminum can be used by modern high-tech equipment to fabricate component parts directly.
A large number of electronic applications make use of aluminum powder. It can be sprayed on to form a thin conductive layer. This makes it an excellent choice for the creation of conductive pathways in certain sorts of mass-produced electrical devices, most notably solar cells and some types of light-emitting diodes.
Powdered aluminum is also added to many paints. It can be added to other colors to produce a more metallic sheen, or can be used on its own. Aluminum can produce a dramatic silver appearance when added to paint. In addition to being used in paint, aluminum can provide similarly striking results when used in cosmetics, and some types of makeup designed to have a metallic appearance make use of aluminum compounds.