Pressure effect on the physical properties of 413-type MAX phase compound Nb4AlC3: Insights from DFT simulation

This article discusses the physical properties of the Nb4AlC3 MAX phase compound under the influence of pressure ranging from 0 to 100 GPa via the calculation of structural, mechanical, thermal, and optoelectrical properties by utilizing the density functional theory (DFT). Under the studied pressure range, the phase Nb4AlC3 is mechanically stable and various elastic moduli show a linear increase with pressure; while the machinability and dry lubricity show opposite cases. Nb4AlC3 shows brittle nature up to 20 GPa pressure, and after 20 GPa, Nb4AlC3 transits to ductile, and then the ductility increases with the further increase of pressure. Metallic feature is ensured from the band structure and density of states calculations as the valence band cross the Fermi level. The average reflectivity is more than 60% (from 0 to 100 GPa) which makes a capable solar heating reducing agent. The Debye temperature, minimum thermal conductivity, and melting point of the Nb4AlC3 compound have a linear increase response with pressure and the application of this compound as favorable thermal barrier coating (TBC) material.