Constitutional and thermal point defects in B2 NiAl

By P. Korzhavyi, A. Ruban, A. Lozovoi, Y. Vekilov, Igor A. Abrikosov, Börje Johansson. 2000

148 citations recorded by the source corpus.

The formation energies of point defects and the interaction energies of various defect pairs in NiAl are calculated from first principles within an order N, locally self-consistent Green's-function method in conjunction with multipole electrostatic corrections to the atomic sphere approximation. The theory correctly reproduces the ground state for the off-stoichiometric NiAl alloys. The constitutional defects (antisite Ni atoms and Ni vacancies in Ni-rich and Al-rich NiAl, respectively) are shown to form ordered structures in the ground state, in which they tend to avoid each other at the shortest distance on their sublattice. The dominant thermal defects in Ni-rich and stoichiometric NiAl are calculated to be triple defects. In Al-rich alloys another type of thermal defect dominates, where two Ni vacancies are replaced by one antisite Al atom. As a result, the vacancy concentration decreases with temperature in this region. The effective defect formation enthalpies for different concentration regions of NiAl are also obtained.

Subfields: Atmospheric Science, Atomic and Molecular Physics, and Optics, Mechanical Engineering

View Paper: https://www.semanticscholar.org/paper/51c8fbce202b34f0f65c3bcf849d3e4291eb8c6d

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

  1. Ali Alavi

Citations in the corpus