Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
797678 | Mechanics of Materials | 2010 | 11 Pages |
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.