Mechanical and electronic properties investigation of Ti₈Pt₇Cu for high temperature applications: A first-principle approach

Materials Modelling Centre, University of Limpopo, Private Bag X 1106, Sovenga, 0727, South Africa,

^* Corresponding author: mordecai.mashamaite@ul.ac.za

Abstract

The martensitic transformation of TiPt is much higher, at approximately 1273 K and this is considered to be of potential technological interest for elevated temperature applications. Previous studies showed that the 50:50 B2 TiPt alloy is mechanically unstable at 0K. The supercell approach is used to substitute Pt with Cu 6.25 at. % on the B2 TiPt binary alloy to evaluate their structural and mechanical properties. The addition of Cu 6.25% reduces the lattice parameter due to the atomic radius. The TiPt_43.75Cu_6.25 alloy is thermodynamically stable, with negative ΔH_f (-0.693 eV/atom). The elastic constant C₁₁, Bulk and Shear moduli were used to investigate the melting point, Debye temperature and Vickers’s hardness. The Debye temperature at 170 K confirmed that TiPt_43.75Cu_6.25 alloys have higher modulus and melting point. The calculated Bulk modulus suggests that Cu strengthen the cubic TiPt. The electronic properties are discussed based on the predicted density of states. The Phonon dispersion of the TiPt_43.75Cu_6.25 alloys is also calculated.