Electrical aspects of the spark-plasma sintering of TiN–TiB2 composite. II. Effect of alternating current on the spark-plasma sintering of TiH2 + BN powder mixture

The effect of alternating current on the formation of phases and structure during the synthesis of TiN + TiB2 composite by spark-plasma sintering of TiH2 + BN powder mixtures employing a superposition of alternating and direct currents is studied. The sintering leads to composites with semiconductor and dielectric phases (Ti and BN oxides) if a direct current is used and to TiN + TiB2 composite with metallic conductivity if a superposition of direct and alternating currents is used. The alternating current intensifies the ion electromigration between particles during spark discharge. This accelerates the decomposition of α-BN by atomic hydrogen and, as a result, intensifies the formation of TiN + TiB2 composite.