کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1560221 1513906 2015 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Bridging time-scales: Grain boundary sliding constitutive law from atomistics
ترجمه فارسی عنوان
مقیاس زمانی برآورد: قانون قانونی لغزش مرزی دانه از اتومیسم
کلمات کلیدی
مرز دانه کشویی، شبیه سازی اتومیستیک، پدیده خزش قانون اساسی
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مکانیک محاسباتی
چکیده انگلیسی

Grain boundary sliding is the key deformation and damage mechanism for high temperature deformation of crystalline materials impacting, thus, applications ranging from nuclear reactors to aircrafts. Despite decades of research—theoretical and experimental—a definitive atomistic understanding of this phenomenon has been elusive. The primary bottleneck is the fact that conventional molecular dynamics can only address pico-to-nano seconds of material physics while the characteristic relaxation times for creep phenomena (including grain boundary sliding) are several orders of magnitude slower. In this letter, we use a fresh approach based on a recently developed potential energy surface sampling method that allows us to bridge long time scales and, for the first time, develop a physically reasonable constitutive law. Our results show a dramatic improvement over what can be gleaned from conventional molecular dynamics and provide insights on the relative merits of existing theories of grain boundary sliding. Our simulations (based on a prototypical metal, Al) answer important questions such as (i) is there a threshold stress for grain boundary sliding?, (ii) what is the form of constitutive law for grain boundary sliding? and others.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Computational Materials Science - Volume 104, 15 June 2015, Pages 200–204
نویسندگان
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