Effect of Compressive Strain Rate on Auxetic Foam

Auxetic foams have previously been shown to benefits including higher indentation resistance than their conventional counterparts, due negative Poisson’s ratio, making them better at resisting penetration by concentrated loads. The ratio and Young’s modulus of auxetic open cell rarely measured the high compressive strain rates typical during impacts energy absorbing material in sporting protective equipment. closed are less common only quasi-static characteristics reported. It is, therefore, unclear how foam, associated such as increased low rates, would transfer expected under impact. aim this study was measure effect rate on stiffness foam. polymer were fabricated, then compression tested ~80% applied up 200 s−1, with ratios obtained from optical full-field mapping. Open foam ranged −2.0 0.4, a narrower range −0.1 0.3 for approximately halved magnitude between minimum maximum rates. moduli 0.02 0.09 MPa, whereas ~1 which is like doubled highest s−1.