Abstract
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.
Original language | English (US) |
---|---|
Pages (from-to) | 852-862 |
Number of pages | 11 |
Journal | Mechanics of Materials |
Volume | 42 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2010 |
Keywords
- Cylindrical nanovoids
- Nanoporous materials
- Surface energy
- Surface stress
- Yield function
ASJC Scopus subject areas
- General Materials Science
- Instrumentation
- Mechanics of Materials