Parts produced using powder metallurgy are becoming increasingly important, particularly in the automobile industry. For the production of sintered parts, metal powders are mixed with small quantities of additives such as waxes and graphite. These powder mixtures are then pressed unter high pressure into so-called green compacts.
As part of this process, graphite ensures reduced wear of the press die and provides internal lubrication within the powder mixture. As a result, graphite makes maximum compression possible. In the sintering process, in which the green compacts are heated to slightly below melting point, the material is then compressed further. Moreover, fine graphite goes into solution in the metal and in doing so increases the mechanical strength of the workpiece.