Microstructure and microtexture of induction sintered copper-based powder metal parts

In this study induction heating was used to sinter copper powders admixed with Acrawax. Two types of powders were used, one with uniform particle size of 25 µm and the other with a bimodal distribution of 20 µm and 60 µm particle sizes. Two heating rates and two dwell times were used to investigate the effects of processing parameters on the microstructure and microtexture of these powders. The results show that induction sintering is a potential sintering method for powder metal parts, however, optimal processing parameters/ conditions such as temperature, heating rate, sintering time, have to be determined to ensure the parts are sintered properly. Induction sintering for 6 min at a rate of 100°C/min developed a microstructure that had lower pore density by ~50% less than conventionally sintered parts. On the other hand, rapid heating cause poor sinterability, and unequal-sized powder promote coarsening and hot spots.