کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1447776 988654 2010 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Nanoscale contact plasticity of crystalline metal: Experiment and analytical investigation via atomistic and discrete dislocation models
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Nanoscale contact plasticity of crystalline metal: Experiment and analytical investigation via atomistic and discrete dislocation models
چکیده انگلیسی

Nanoscale incipient plastic deformation in crystalline metals occurs as the result of the collective motion of dislocations. It is known as “nanoplasticity” and is recognized as the elementary process of the macroscopic deformation. Abrupt increases in indent displacements called displacement bursts were observed in recent nanoindentation experiments; that is, the specific behavior for nanoplasticity. In the present study, experimental tests are first conducted to educe the unique nature of the nanoscale deformation. Subsequently, large-scale atomistic simulations are performed to predict the incipient plastic deformation and a new discrete dislocation model combined with the boundary element analysis is constructed to capture the collective motion of the dislocations. Our results suggest that the incipient plastic deformation requires much higher critical shear stress than the theoretical shear strength due to high compressive stress distribution beneath the indenter, and that the displacement burst is induced by surface rearrangement corresponding to hundreds of dislocation dipoles.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 58, Issue 8, May 2010, Pages 3096–3102
نویسندگان
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