TY - JOUR
T1 - Surface energy effects on the yield strength of nanoporous materials containing nanoscale cylindrical voids
AU - Goudarzi, T.
AU - Avazmohammadi, R.
AU - Naghdabadi, R.
N1 - Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2010/9
Y1 - 2010/9
N2 - Surfaces and interfaces behave differently from their bulk counterparts especially when the dimensions approach small scales. The recent studies have shown that the surface/interface free energy (surface stress) plays an important role in the effective mechanical properties of solids with nanosized inhomogeneities. In this work, within a micromechanical framework, the effect of surface stress is taken into account to obtain a macroscopic yield function for nanoporous materials containing cylindrical nanovoids. Gurtin-Murdoch model of surface elasticity is incorporated in the generalized self-consistent method to obtain a closed-form expression for the transverse shear modulus of transversely isotropic nanoporous materials. Using the transverse shear modulus of a nanoporous material along with the other effective elastic properties, an energy-type overall yield function for such a nanoporous material is derived. Additionally, performing numerical examples for various loading cases, it is shown that the surface stress has a significant influence on the yield surfaces of the nanoporous material comprised of compressible/incompressible matrices, especially for voids radii less than 10 nm.
AB - Surfaces and interfaces behave differently from their bulk counterparts especially when the dimensions approach small scales. The recent studies have shown that the surface/interface free energy (surface stress) plays an important role in the effective mechanical properties of solids with nanosized inhomogeneities. In this work, within a micromechanical framework, the effect of surface stress is taken into account to obtain a macroscopic yield function for nanoporous materials containing cylindrical nanovoids. Gurtin-Murdoch model of surface elasticity is incorporated in the generalized self-consistent method to obtain a closed-form expression for the transverse shear modulus of transversely isotropic nanoporous materials. Using the transverse shear modulus of a nanoporous material along with the other effective elastic properties, an energy-type overall yield function for such a nanoporous material is derived. Additionally, performing numerical examples for various loading cases, it is shown that the surface stress has a significant influence on the yield surfaces of the nanoporous material comprised of compressible/incompressible matrices, especially for voids radii less than 10 nm.
KW - Cylindrical nanovoids
KW - Nanoporous materials
KW - Surface energy
KW - Surface stress
KW - Yield function
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U2 - 10.1016/j.mechmat.2010.07.006
DO - 10.1016/j.mechmat.2010.07.006
M3 - Article
AN - SCOPUS:77956163912
VL - 42
SP - 852
EP - 862
JO - Mechanics of Materials
JF - Mechanics of Materials
SN - 0167-6636
IS - 9
ER -