A first-principles study of hypothetical Ti4AlB3 and V4AlB3 phases

In this paper, we employed the pseudopotential plane-waves method to investigate the structural, elastic properties, bond stiffness and thermal properties for hypothetical layered ternary ceramic Ti4AlB3 and V4AlB3 phases. By calculating the formation energy and elastic constants, the stability of these two hypothetical structures was discussed from the energetic and mechanical point of view. The B/G ratio and Poisson ratio were calculated to discuss the bond composition of Ti4AlB3 and V4AlB3 compounds. In addition, we calculated the bond stiffness for different bonds in Ti4AlB3 and V4AlB3. The ratio of the weakest bond stiffness to the strongest bond stiffness was presented to explore their mechanical properties. What's more, by calculating longitudinal, transverse sound, mean sound velocities, and the Debye temperatures, we discussed the thermal conductivity of hypothetical Ti4AlB3 and V4AlB3 phases.