Structure and mechanical properties of Al–Ni–Ti amorphous powder consolidated by pressure-less, pressure-assisted and spark plasma sintering

Abstract

Attempts have been made to prepare highly dense bulk Al-based nanocomposite consisting of evenly distributed nano-intermetallic particles and amorphous phase by consolidating mechanically alloyed amorphous Al 88Ni 6Ti 6 powder using spark plasma sintering (SPS), hot-pressing and pressure-less sintering techniques. SPS technique has been most effective in comparison to other two processes in getting better homogeneity of microstructural features, densification and mechanical properties due to lower sintering temperature and time, hindering excessive crystallization of amorphous phase and grain growth of formed nanocrystals. This helps in producing optimum microstructure consisting of homogeneous distribution of nanocrystalline intermetallic phase and remaining amorphous phase as revealed by detailed electron microscopy and nano-indentation tests.