29.6.2010 Pressing & Sintering

The use of a new machinability enhancer for improving the machinability of pre-alloyed powder metal components without detrimental effects on the material characteristics

Even though powder metallurgy (PM) offers near net-shape capability, often secondary machining is necessary to meet tolerance and surface finish requirements. Besides compositions of material itself, processing conditions and the resultant microstructures play a large role in determining the machinability of a component. Machinability enhancers are usually added to achieve better machinability. As alloying elements and content increase, machining of PM components becomes more difficult and traditional machinability enhancers become less effective. In this paper, a newly developed machinability enhancer with the potential of improving the machinability of prealloyed powder metal components while minimizing potential effects on material properties is examined. Results of this study demonstrate the benefits of the newly developed machinability enhancer, significantly improving the machinability without detrimental effect to sintered strength. This is accomplished without staining while maintaining the same corrosion resistance as the material without any additive.