Abstract
Diffusion in the Ll2 structure is investigated by means of atomistic kinetic Monte Carlo simulations on a rigid lattice. Special attention is devoted to the influence of the composition on the diffusion process in a binary alloy. We observe that two diffusion mechanisms resulting from the interactions of vacancies with antisites located on both sublattices allow for the displacement of the minority element and can enhance the diffusivity of the majority element. The respective contributions to the diffusion process of these two mechanisms strongly depend on the temperature and on the degree of departure from the stoichiometric composition. These two mechanisms can explain the minimum nickel diffusivity experimentally observed around the stoichiometic composition in Ni3Al compounds and the suspected lower activation energy for gallium than for nickel in Ni3Ga.
Original language | English (US) |
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Pages (from-to) | 2243-2257 |
Number of pages | 15 |
Journal | Philosophical Magazine A: Physics of Condensed Matter, Structure, Defects and Mechanical Properties |
Volume | 79 |
Issue number | 9 |
DOIs | |
State | Published - Sep 1999 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- General Materials Science
- Condensed Matter Physics
- Physics and Astronomy (miscellaneous)
- Metals and Alloys