Identification of the mechanical behaviour of low density hyperelastic polymeric foams from full-field measurements

This paper presents a methodology aimed at the identification of the mechanical behaviour of hyperelastic low density polymeric foams using digital image correlation and the Virtual Fields Method. First, a simple bending/shear test enables the identification of the elastic parameters at low strain levels. Then, a uniaxial compression test is performed to identify the parameters of an Ogden-type law (hyperelastic). The strain fields exhibit strong localization caused by the elastic collapse of the cells clearly indicating that an approach based on global force/displacement curves will fail to provide intrinsic material parameters (structural effect). This is still very much a preliminary study but it clearly shows the potential of the approach for this type of materials.