Substitutional diffusion in multicomponent solids with non-ideal sources and sinks for vacancies

0352150 - ÚFM 2011 RIV GB eng J - Journal Article
Fischer, F. D. - Svoboda, Jiří
Substitutional diffusion in multicomponent solids with non-ideal sources and sinks for vacancies.
Acta Materialia. Roč. 58, č. 7 (2010), s. 2698-2707. ISSN 1359-6454. E-ISSN 1873-2453
R&D Projects: GA MŠMT(CZ) OC10029
Institutional research plan: CEZ:AV0Z20410507
Keywords : Substitutional diffusion * Vacancies * Annihilation
Subject RIV: BJ - Thermodynamics
Impact factor: 3.781, year: 2010

Based on previous work by the authors the diffusion equations for a multicomponent solid are derived. Generation and annihilation of vacancies are described by an evolution law which is directly coupled with an eigenstrain rate. Manning’s correlation factor f is used in the kinetic factor for diffusion of vacancies. In addition to presentation of the diffusion equations, a rigorous treatment of the boundary conditions, assuming no or an ideal source and sink for vacancies at the surface, is presented. As an instructive example development of the site fractions of the components and the eigenstress state are demonstrated for a multicomponent chemically inhomogeneous layer on a substrate. Both the role of nonlinear terms and the correlation factor f in the diffusion equations are studied. Computational procedures to calculate to the proper boundary conditions are also outlined.
Permanent Link: http://hdl.handle.net/11104/0191729