کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1449728 988713 2007 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Dipole formation due to ion-exchange processes at the metal-ceramic Al/MgAl2O4 (0 0 1) interface
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Dipole formation due to ion-exchange processes at the metal-ceramic Al/MgAl2O4 (0 0 1) interface
چکیده انگلیسی

First-principles density functional calculations were performed on the coherent (0 0 1) interface between spinel (MgAl2O4) and aluminium, focusing on the ion-exchange reaction at the interface. The exchange reaction occurs by diffusion of magnesium and aluminium ions in opposite directions across the interface, at a rate controlled by the surface-to-volume ratio of the MgAl2O4 particles. We investigate the hypothesis that the reaction may involve a net charge transfer, leading to the formation of an interface electric dipole, with a possible influence on the mechanical properties of the Al/MgAl2O4 composite. Our analysis of the electronic charge density accompanying the ion exchange reveals an electric dipole at the interface. Its formation is shown to be a consequence of the interface electronic structure, taking the form of screening effects occurring locally at the substitutional Al site and more diffusely over the whole interface region.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 55, Issue 17, October 2007, Pages 5813–5821
نویسندگان
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