Laser measurement of dimensional change sin powder metallurgy manufacturing processes

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Near-net-shape processes are alternative methods of manufacturing products which provide minimal raw material wastage and little need for secondary machining or finishing. Powder metallurgy (PM) technologies are some of the most popular near-net-shape processes, where powdered metals are pressed into complex product geometries. Using the popular 'press-and-sinter' production process, powdered metal is pressed (compacted) in a die to the desired shape. These 'green compacts' are then heated in a controlled environment (sintered). Sintering sets the part microstructure and heavily influences its mechanical properties. However, after each of these processes the part often exhibits dimensional changes which, given the primary attractiveness of PM technologies, greatly lowers part quality. Two principal dimensional changes are springback and warping. After compaction, the part slightly enlarges as the powder relaxes, which is known as springback, and after sintering the part often warps or distorts considerably.