Historical traceability of metal powder

The production and application of metal powders have a long history. In ancient times, gold, silver, copper, bronze and some of its oxide powders were used as coatings for the coloring and decoration of pottery, jewelry and other utensils. At the beginning of the 20th century, American W.D. Coolidge used hydrogen to reduce tungsten oxide to produce tungsten powder to produce tungsten wire, which was the beginning of modern metal powder production. After that, various powders such as copper, cobalt, nickel, iron and tungsten carbide were prepared by chemical reduction method, which promoted the development of early powder metallurgy products (oil-containing porous bearings, porous filters, hard alloys, etc.); The carbonyl method is used to prepare iron powder and nickel powder. In the 1930s, iron powder was first prepared by eddy current grinding, and then iron powder was produced by solid carbon reduction. The cost was very low. The molten metal atomization method also appeared in the early 1930s. This method was originally used to prepare low-melting metals such as tin, lead, aluminum and other powders. In the early 1940s, it was developed to prepare iron powder by atomization with high-pressure air. In the 1950s, alloy steel and various alloy powders were prepared by high-pressure water atomization. In the 1960s, a variety of atomization methods were developed to produce high-alloy powders, which promoted the development of high-performance powder metallurgy products. Since the 1970s, a variety of gas-phase and liquid-phase physicochemical reaction methods have emerged to prepare coated powders and ultrafine powders for important applications.