کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1450023 988720 2008 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influence of Pb segregation on the deformation of nanocrystalline Al: Insights from molecular simulations
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Influence of Pb segregation on the deformation of nanocrystalline Al: Insights from molecular simulations
چکیده انگلیسی

Molecular dynamics straining simulations using a two-dimensional columnar model were run for pure Al with grain sizes from 5 to 30 nm, and for 10 nm grain size Al–Pb alloys containing 1, 2 and 3 at.% Pb. Monte Carlo simulations showed that all the Pb atoms segregate to the grain boundaries. Pb segregation suppresses the nucleation of partial dislocations and twins during straining. At 3 at.% Pb, no dislocations or twins are observed throughout the straining history. It also appeared that Pb tends to segregate to the same locations in grain boundaries that were favorable for partial dislocation emission. Grain boundaries with Pb segregates were very robust against dissociation during straining compared to pure Al. The yield stress determined from stress–strain curves showed a decrease with increasing Pb content, supporting a similar observation for the hardness change measured on nanocrystalline Al–Pb alloys.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 56, Issue 17, October 2008, Pages 4750–4761
نویسندگان
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