Molten salt-assisted synthesis of carbo-nitride TiC0.5N0.5 and MAX phases Ti2AlC0.5N0.5 and Ti3AlCN at low temperature under different atmospheres

Abstract

Transition metal-based carbo-nitride solid solution phases have wide application in electrical, electronic, automotive, and refractory industries due to the excellent combination of metallic and ceramic properties. Mainly, carbo-nitride phases were synthesized by high-temperature solid-state diffusion, carbothermal reduction-nitridation, HIP, SHS, pressureless sintering at high temperature, etc. All the methods required considerable investment and production costs, limiting their application in the larger area of research. To overcome all the problems related to the synthesis, one simple, cost-effective, energy-efficient, and environmentally friendly method is required where synthesis will be carried out at a lower temperature with a shorter soaking time. Molten salt-assisted synthesis method fulfils these requirements by accelerating the diffusion rate for phase formation through a chemically inert liquid medium. In this manuscript, carbo-nitride TiC0.5N0.5 and MAX phases Ti2AlC0.5N0.5 and Ti3AlCN have been synthesized using this method with a different atmosphere (Ar, N2, and Air) at a relatively lower temperature with a shorter period of time and characterized by XRD, SEM, particle size analyzer, and HRTEM. The relative density was measured by Archimedes’ principle in case of all the samples and electrical conductivity of the respective samples was determined by the four-probe method.