Phases distribution dependent strength in metallic glass–aluminium composites prepared by spark plasma sintering

Composites with volume fraction from 10 vol.% to 90 vol.% were prepared by spark plasma sintering (SPS) of mixing of aluminium and metallic glass (Zr57Cu20Al10Ni8Ti5) powders with similar particle size. These materials show gradual evolution of their mechanical behaviour. First, monotonous but non linear variation of the strength is observed. That reveals two different mechanisms describing the dependence of strength with the composition and architecture. Second, stress–strain curves successively show, from low to high Al content, absence of plasticity, plasticity with intensive decrease of strength related to local damaging, and finally plasticity with work hardening. The mechanical behaviour evolutions are geometrically and analytically modelled. This reveals change in behaviour at the expected 3-dimensional percolation thresholds for a random spatial distribution of two phases.