Simultaneous pulsed current activated combustion synthesis and densification of NbSi2-SiC composite

Dense ultrafine NbSi2-SiC composite was synthesized by the pulsed current activated combustion synthesis (PCACS) method within 3 min in one step from mechanically activated powders of NbC and 3Si. Simultaneous combustion synthesis and densification were accomplished under the combined effects of a pulsed current and mechanical pressure. Highly dense NbSi2-SiC composite with relative density of up to 97% was produced under simultaneous application of a 60 MPa pressure and the electric current. The average grain size and mechanical properties (hardness and fracture toughness) of the composite were investigated.