کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1448120 988665 2009 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Grain-boundary shear-migration coupling. II. Geometrical model for general boundaries
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Grain-boundary shear-migration coupling. II. Geometrical model for general boundaries
چکیده انگلیسی

Grain boundary-mediated plasticity is now a well-established phenomenon, especially in fine-grained or nanocrystalline metals. It has been described in several models, but most of these apply to very exclusive configurations such as symmetrical grain boundaries, or grain boundaries that possess a specific coincidence orientation relationship. In real polycrystals, grain boundaries have random orientations, and the current models cannot account for the shear associated with their migration (see part I of this study [1]). The present work presents a model of shear-migration coupling in which grain boundaries do not have specific orientation relationships. It consists in defining couples of shear and rotation values, able to transform one lattice orientation into another, regardless of the type of boundary that separate them. This purely geometrical model can be seen as a generalized formulation of the existing shear coupling theories. No long-range diffusion is involved, but very localized atomic shuffling is generally necessary in the core of mobile interfacial dislocations.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 57, Issue 8, May 2009, Pages 2390–2402
نویسندگان
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