Characterization of auxetic and mechanical behaviours of auxetic composites developed using star knitted structures

Abstract

This work evaluates the auxetic behaviour of composite materials produced from weft-knitted fabrics made from high-tenacity para-aramid (p-AR) and polyamide 6.6 (PA) fibres, which have proven to present negative Poisson’s ratios (NPR). Composites were produced by reinforcing an epoxy resin with those developed fabrics and the degree to which they were able to preserve the previous auxetic behaviour of the fibrous reinforcements investigated in order to obtain a new type of auxetic materials, reinforced with re-entrant star designed fabrics, that could present higher mechanical performance due to its NPR behaviour.