DFT calculations of elastic, electronic and thermal properties of TiB2Mo

Abstract

Ceramics are materials with good mechanical properties; however, low fracture toughness, intrinsic brittleness and poor resistance against oxidation at high temperatures are challenges limiting their applications. TiB2Mo is a ceramic material whose all elastic properties have not been calculated. In this study, we investigated the elastic, electronic and thermal properties of TiB2Mo structure using first principles calculations. All first principles calculations were based on the density functional theory as implemented in Quantum ESPRESSO code with the help of Thermo-pw as a post-processing code. Obtained lattice parameters of TiB2Mo structure were in good agreement with other previous theoretical studies. TiB2Mo structure was found to be mechanically and dynamically stable at ground state conditions. The results also show that TiB2Mo is brittle, anisotropic and metallic in nature. Based on the calculated Vicker's hardness Hv, we noted that TiB2Mo is classified as a hard material with fracture toughness of above 7 MPam0.5; therefore, it is a promising ultra-high temperature ceramic.