ALUMINUM POWDERS and ALUMINUM alloys are produced almost exclusively by gas atomization. For most applications, the atomizing gas is compressed air; however, in some special cases, inert gases (helium, nitrogen, and argon) are used. Between 25 and 30 countries in the world are known to have production facilities for aluminum powder at an estimated total capacity of 200,000 tons per year (Ref 1). A large portion of this capacity is in North America where annual shipments are about 40,000 tons (Ref 2). Atomized aluminum powders are used in a variety of applications that include pyrotechnics, explosives, rocket fuel, thermite welding, aluminothermic reduction, chemical processes (as catalyst or reagent), additives for lightweight concrete, pharmaceuticals, and pigments for paints and printing inks. With few exceptions, the demand is for unalloyed powder of various standards of purity. Aluminum alloy P/M, historically a small percentage (about 1%) of the total powder market, has been enjoying a revival in recent years in automotive applications because of the need to reduce weight, lower emissions, and boost fuel economy. Viable P/M applications include engine cam caps and air conditioning compressor parts. Powder metallurgy offers competition to wrought aluminum castings and stampings because of its net shape advantage.

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