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Newly Synthesized Ta‐Based MAX Phase (Ta 1− x Hf x ) 4 AlC 3 and (Ta 1− x Hf x ) 4 Al 0.5 Sn 0.5 C 3 (0 ≤ x ≤ 0.25) Solid Solutions: Unravelling the Mechanical, Electronic, and Thermodynamic Properties
Author(s) -
Ali Md. Ashraf
Publication year - 2021
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.202000307
Subject(s) - debye model , bulk modulus , materials science , shear modulus , lattice constant , anisotropy , thermodynamics , max phases , electronic structure , solid solution , density of states , crystallography , condensed matter physics , chemistry , composite material , physics , metallurgy , carbide , quantum mechanics , diffraction , optics
Investigation of the mechanical, electronic, and thermodynamic properties of recently synthesized (Ta 1− x Hf x ) 4 AlC 3 and (Ta 1− x Hf x ) 4 Al 0.5 Sn 0.5 C 3 (0 ≤ x ≤ 0.25) solid solutions is conducted using density functional theory for the first time. The computed lattice constants are in good agreement with prior results. The calculated stiffness constants are used to check the mechanical stability of the studied compositions. The bulk modulus ( B ), shear modulus ( G ), and Young's modulus ( Y ) are found to be influenced by Hf and Sn substitution. The titled solid solutions are brittle in nature. The 3D presentations of elastic moduli and elastic anisotropy factors are used to disclose the anisotropic mechanical features of the considered compositions. The electronic band structure, density of states, and charge density mapping (CDM) show the metallic nature, the contribution from different states to electronic conductivity, and atomic bonding characteristics. The electronic band structure and CDM are also used together to investigate the change in bonding strength due to Hf and Sn substitutions. The Debye temperature (Θ D ), minimum thermal conductivity ( K min ), Grüneisen parameter ( γ ), and melting temperature ( T m ) of the studied solid solutions are estimated and analyzed. A good correlation is found between the mechanical and thermodynamic properties.