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

Abstract

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. (C) 2007 Elsevier Ltd and Techna Group S.r.l. All rights reserved.