Spark plasma sintering of Al–Cr–Fe quasicrystals: Electric field effects and densification mechanism

In this study, gas atomized Al–Cr–Fe powders were consolidated using spark plasma sintering (SPS). Hypotheses about the densification mechanism were proposed and effects of the electric field were investigated. The densification is initially controlled by particle rearrangement and then by dislocation motion. The comparison of X-ray diffraction patterns of the SPSed sample and the sample annealed in the vacuum oven shows that SPS process generates a higher amount of decagonal Al–Cr–Fe. It is proposed that such effect can be attributed to the decrease in the activation energy for forming the critical nuclei in the electric field.