Mechanical properties of low density polymeric foams obtained from full-ﬁeld measurements
Laboratoire de Mécanique et Procédés de Fabrication, Arts et
Metiers ParisTech, Rue St Dominique, B.P.508, 51006
Châlons en Champagne,
This exploratory paper presents some preliminary results on the use of fullﬁeld deformation measurements on low density polymeric foams to identify the evolution of Poisson’s ratio with compressive strain. Two types of foams were tested: a standard low density polyurethane foam and an auxetic foam manufactured from a similar precursor. 2D digital image correlation was used to measure the strain ﬁeld at the specimens surfaces. Then, Poisson’s ratios were identiﬁed using a dedicated inverse method called the Virtual Fields Method (VFM) and the results compared with the standard approaches. The results illustrate the advantages of the VFM compared to the standard procedure. It was also found that for the standard foam, very strong localization eﬀects resulted in biased Poisson’s ratio evaluation. It was shown that this could be corrected by taking into account these localization eﬀects thanks to the full-ﬁeld information.
© Owned by the authors, published by EDP Sciences, 2010