Metal powder refers to the metal particle size less than 1 mm. Include a single metal powder, alloy powder, and some with characteristics of metal powder, refractory compounds is the main raw materials of powder metallurgy.
Making and application of metal powder origin. Ancient with gold, silver, copper, bronze and some oxide powder coating, pottery, jewelry, and other instruments used for the color and decoration. At the beginning of the 20th century, americans cooley, ji (W.D.C oolidge) tungsten powder produced by hydrogen reduction of tungsten oxide in making tungsten filament, is the beginning of modern metal powder production. Since then by chemical reduction of the copper, cobalt, nickel, iron, tungsten carbide powder, promoted the early powder metallurgy products (porous bearings, oil filters, hard alloy, etc.); At this time also invented the made of iron powder and nickel powder by carbonyl method. S first take iron powder by using eddy current grinding, then iron powder produced by solid carbon reduction method, the cost is low. Molten metal atomization method emerged in the early 30 s. At first, this method is used to making low melting point metals such as tin, lead, aluminium powder, to 40 s become with high-pressure air atomization for making iron powder. 50 s with high-pressure water spray making alloy and a variety of alloy powder. In the '60 s developed a variety of ways to produce high alloy powder atomization, promoting the development of high performance powder metallurgy products. Since the 70 s, appeared a variety of gas phase and liquid phase physical and chemical reaction method, thus has important use of coated powder and ultrafine powder.
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