Mechanics of hierarchical 3-D nanofoams

¹ Department of Structural Engineering and Geotechnics, Politecnico di Torino - I-10129, Torino, Italy, EU
² Laboratory of Bio-Inspired Nanomechanics ‘‘Giuseppe Maria Pugno’’, Department of Structural Engineering and Geotechnics, Politecnico di Torino - I-10129, Torino, Italy, EU
³ National Institute of Nuclear Physics, National Laboratories of Frascati - Via E. Fermi 40, I-00044, Frascati, Italy, EU
⁴ National Institute of Metrological Research - Strada delle Cacce 91, I-10135, Torino, Italy, EU

^a nicola.pugno@polito.it

Received: 29 July 2011
Accepted: 28 November 2011

Abstract

In this paper, we study the mechanics of new three-dimensional hierarchical open-cell foams, and, in particular, its Young's modulus and plastic strength. We incorporate the effects of the surface elasticity and surface residual stress in the linear elastic and plastic analyses. The results show that, as the cross-sectional dimension decreases, the influences of the surface effect on Young's modulus and plastic strength increase, and the surface effect makes the solid stiffer and stronger; similarly, as level n increases, these quantities approach to those of the classical theory as lower bounds.