کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
797898 1467092 2013 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Surface energy, elasticity and the homogenization of rough surfaces
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی مکانیک
پیش نمایش صفحه اول مقاله
Surface energy, elasticity and the homogenization of rough surfaces
چکیده انگلیسی

The concept of surface energy is widely used to understand numerous aspects of material behavior: fracture, self-assembly, catalysis, void formation, microstructure evolution, and size-effect exhibited by nanostructures. Extensive work exists on deriving homogenized constitutive responses for macroscopic composites—relating effective properties to various microstructural details. In the present work, we focus on homogenization of surfaces. Indeed, elucidation of the effect of surface roughness on the surface energy, stress, and elastic behavior is relatively under-studied and quite relevant to the behavior of both nanostructures and bulk material where surfaces are involved in some form or fashion. We present derivations that relate both periodic and random roughness to the effective surface elastic behavior. We find that the residual surface stress is hardly affected by roughness while the superficial elastic properties are dramatically altered and, importantly, they may also change sign—this has significant ramifications in the interpretation of sensing based on frequency measurement changes. Interestingly, even if the bare surface has a zero surface elasticity modulus, roughness is seen to endow it with one. Using atomistic calculations, we verify the qualitative validity of the obtained theoretical insights. We show, through an illustrative example, that the square of resonance frequency of a cantilever beam with rough surface can decrease almost by a factor of two compared to a flat surface.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of the Mechanics and Physics of Solids - Volume 61, Issue 2, February 2013, Pages 325–340
نویسندگان
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