Density functional theory study of the α → ω martensitic transformation in titanium induced by hydrostatic pressure

Abstract

The martensitic α → ω transition was investigated in Ti under hydrostatic pressure. The calculations were carried out using the density functional theory (DFT) framework in combination with the Birch-Murnaghan equation of state. The calculated ground-state properties of α and ω phases of Ti, their bulk moduli and pressure derivatives are in agreement with the previous experimental data. The lattice constants of α and ω-phase at 0 K were modeled as a function of pressure from 0 to 74 GPa and 0 to 119 GPa, respectively. It is shown that the lattice constants vary in a nonlinear manner upon compression. The calculated lattice parameters were used to describe the α → ω transition and show that the phase transition can be obtained at 0 GPa and 0 K.

Theoretical study of the elastic and thermodynamic properties of Pt_{3}Al with the L1_{2} structure under high pressure

“…The critical value which separates ductile and brittle material is 1.75. The material exhibits a ductile behaviour when the value B /G > 1.75; otherwise, the material behaves in a brittle manner [24,25]. We found that the B /G is 2.89 at 0 GPa and increases with the pressure increase.…”

Significant lattice thermal conductivity reduction following phase separation of the highly efficient Ge x Pb1-x Te thermoelectric alloys

“…At the first stage, determination of the bulk moduli of GeTe and PbTe at 0 K was obtained using ab initio DFT calculations, by applying the third‐order Birch‐Murnaghan equation of state, expressed in Eq. : where E 0 and V 0 are the energy and volume at equilibrium, respectively, V the deformed volume, B 0 the bulk modulus and the derivative of the bulk modulus with respect to the pressure.…”

Atomistic Study of the Role of Defects on α → ϵ Phase Transformations in Iron under Hydrostatic Compression

“…Density functional theory (DFT) results are very important to understand martensitic phase transformations under pressure in different materials [10][11][12][13][14]. The martensitic transformation in titanium has been analyzed and the DFT results are able to describe the experimental results [13][14][15]. DFT calculations [10][11][12] have confirmed the stability of hcp iron under high pressure and revealed the transition barrier of the bcc/hcp phase transformation [12].…”

“…Density functional theory (DFT) results are very important to understand martensitic phase transformations under pressure in different materials [10][11][12][13][14]. The martensitic transformation in titanium has been analyzed and the DFT results are able to describe the experimental results [13][14][15].…”