کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7178101 1467068 2015 27 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A study of conditions for dislocation nucleation in coarser-than-atomistic scale models
ترجمه فارسی عنوان
مطالعه شرایطی که برای خنثی سازی جابجایی در مدلهای سنگینتر از مقیاس اتومیستی انجام شده است
کلمات کلیدی
هسته زدگی، نانو تند، مدل سازی چند بعدی، معیار هسته ای، مکانیک جابجایی،
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی مکانیک
چکیده انگلیسی
We perform atomistic simulations of dislocation nucleation in defect free crystals in 2 and 3 dimensions during indentation with circular (2D) or spherical (3D) indenters. The kinematic structure of the theory of Field Dislocation Mechanics (FDM) is shown to allow the identification of a local feature of the atomistic velocity field in these simulations as indicative of dislocation nucleation. It predicts the precise location of the incipient spatially distributed dislocation field, as shown for the cases of the Embedded Atom Method potential for Al and the Lennard-Jones pair potential. We demonstrate the accuracy of this analysis for two crystallographic orientations in 2D and one in 3D. Apart from the accuracy in predicting the location of dislocation nucleation, the FDM based analysis also demonstrates superior performance than existing nucleation criteria in not persisting in time beyond the nucleation event, as well as differentiating between phase boundary/shear band and dislocation nucleation. Our analysis is meant to facilitate the modeling of dislocation nucleation in coarser-than-atomistic scale models of the mechanics of materials.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the Mechanics and Physics of Solids - Volume 75, February 2015, Pages 76-92
نویسندگان
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