Synthesis of bimetallic carbonitrides (V0.8Ti0.2)(C,N) and its application as a grain refiner

Abstract

We synthesized the bimetallic carbonitride powders (V0.8Ti0.2)(C,N) from carbothermal reaction of V2O5 and TiO2 in N2 atmosphere. The reaction process in the temperature range of 873 K to 1573 K (600 °C to 1300 °C) was investigated by X-ray diffraction (XRD) and by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The formation of (Ti0.2V0.8)(C,N) powders involves the multistep reduction reaction of oxides V2O5 and TiO2, and subsequent nitridation and atom diffusion to form the solid solution. The as-synthesized (V0.8Ti0.2)(C,N) powders are spherical particles with diameters of 1 to 2 µm. By addition of 0.023 wt pct of (V0.8Ti0.2)(C,N) powders, the grains of aluminum ingot were effectively refined to 160 µm in size.