Properties and densification of nanocrystalline MoSi2-Si3N4 composite from mechanically alloyed powders by pulsed current-activated sintering

Nanosized MoSi2 and Si3N4 powders were synthesized from Mo2N and Si powders by high-energy ball milling. A dense nanocrystalline MoSi2-Si3N4 composite was consolidated using the pulsed current-activated sintering (PCAS) method within 3 min period from the mechanically activated MoSi2 and Si3N4 powders. A highly dense MoSi2-Si3N4 composite, with relative density of up to 97%, was produced under the simultaneous application of 80 MPa pressure and 2800 A pulsed current. The mean grain size, hardness, and fracture toughness of the composite were investigated.