Powder Metallurgy

Abstract Johnson, Peter K. (Metal Powder Industries Federation, APMI International). Powder metallurgy uses metal powder as the raw material to manufacture products, especially precision metal shapes and parts. The process is cost effective in producing simple or complex parts at or very close to final dimensions. These parts are finding increasing consumer and industrial applications in automobile engines and transmissions, aerospace hardware, home appliances, power tools and hardware, computer disk drives, and surgical implements. Powder metallurgy products include tungsten lamp filaments, self‐lubricated bearings, various magnet, tools, metal‐matrix composites, and electrical components. Use of the technology continues to grow in importance. Superalloys intermetallics, and nanoscale powders are all formed from powder techniques. Processes for producing metal powders are reviewed, and powder characteristics, are discussed. Basically a chipless metalworking process, powder metallurgy typically uses more than 97% of the starting raw materials in the finished part. The new‐shape advantage makes it a process of choice for precision metal components at reduced manufacturing costs. Various production processes for consolidating metal powders into shapes such as traditional compacting and sintering, rapid solidification, cold and hot isostatic pressing, metal injection molding, powder forging and rolling, and spray forming are reviewed.