vibrations and stabilization of the beta phase in Ni-Ti shape-memory alloy

Condensed Matter journal club

vibrations and stabilization of the beta phase in Ni-Ti shape-memory alloy

  • Event time: 11:30am
  • Event date: 1st October 2010
  • Speaker: Bengt Tegner (Formerly School of Physics & Astronomy, University of Edinburgh)
  • Location: Room 2511,

Event details

Abstract

Lattice dynamical methods used to predict phase transformations in crystals typically evaluate the harmonic phonon spectra and therefore do not work in frequent and important situations where the crystal structure is unstable in the harmonic approximation, such as the beta structure when it appears as a high-temperature phase of the shape memory alloy Ni-Ti. Here it is shown by self-consistent ab initio lattice dynamical calculations that the critical temperature for the premartensitic R-to-beta phase transformation in Ni-Ti can be effectively calculated with good accuracy, and that the beta phase is a result primarily of the stabilizing interaction between different lattice vibrations
Phys. Rev. B 81 092201 (2010)

Authors

Petros Souvatzis, Dominik Legut, Olle Eriksson, and Mikhail I. Katsnelson