Scale-up of Transformation of Negative Poisson's Ratio foam: Slabs

Abstract

This paper presents an experimental study performed on the scale-up of processing of negative Poisson 's ratio foam. These materials become thinner under compression and fatter under tension, opposite to ordinary materials. The transformation process consists of triaxial compression combined with heat treatment. Transformed foam cells have a concave or "re-entrant" shape. Scaleup is achieved by use of a modified mould assembled around the foam slab and longer processing times. Foam with a distribution of cell sizes was transformed in small block and large slab forms. These blocks and slabs exhibited a negative Poisson's ratio.