Spark plasma sintering behavior of pure aluminum depending on various sintering temperatures

We have successfully fabricated high-density pure aluminum (Al) bulk by means of a spark-plasma-sintering (SPS) process. The relative density of Al was enhanced as the sintering temperature of the SPS process increased. During the SPS process for pure Al power, the Al oxide layer on the surface of the Al particle was partially broken by the microplasma and applied pressure. The microstructures of the spark-plasma-sintered compacts obtained at various temperatures were observed by optical microscopy, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy. We believe that the pinning effect, rapid heating cycle, and applied pressure played an important role in restraining the particle growth despite the increase in sintering temperature. It is feasible that the employed SPS process could be very useful to achieve fully densified Al compact.