Advanced Light Alloys and Composites pp 41-46 | Cite as
Atomic Mechanisms of Diffusion in Ni3Al
Abstract
Atomic mechanisms of selfdiffusion in Ni3A1 are theoretically studied. Available experimental data on Ni diffusion are shown to be generally consistent with a model of Ni vacancy movements in the Ni sublattice. At present, the problem of Al self-diffusion cannot be certainly clarified owing to a lack of reliable experimental data. A model of Al atom diffusion by anti-structure defects via so-called anti-structure bridges is suggested. The contribution of anti-structure defects increases with a deviation from the stoichiometric composition and strongly depends on the long-range order. A modified approach to calculate equilibrium defect concentrations is considered and the effect of ordering on Al diffusion is investigated.
Keywords
Intermetallic Compound Vacancy Concentration Atomic Mechanism Impurity Diffusion Impurity Diffusion CoefficientPreview
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