Powder metallurgy (PM) is a method known for producing components of great complexity i.e. to near netshape and to very close tolerances. Nevertheless, some components require at least some type ofmachining operation to fully obtain the definitive shape and geometry, e.g. holes perpendicular to powderpressing direction, bevels, slots and threads. Machining operations are also used to fulfil the demands ofhigher surface quality and to further improve tolerances.Once the decision to carry out a machining operation of a PM steel component has been made the need tounderstand the characteristic of machinability will be inevitable. However, machinability of PM steel willnot be influenced by the material properties alone but by all parameters concerning the machiningoperation, i.e. tool grade and geometry, cutting speed and machine stability.This paper describes how machinability for some sintered PM steels can be improved by optimizingdifferent parameters, e.g. tool material, additives and cutting fluid.
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