Determination of Material Parameters of EVA Foam under Uniaxial Compressive Testing Using Hyperelastic Models

Abstract

The objective of this research was to determine the mechanical parameter from EVA foam and also investigate its behavior by using Blatz-Ko, Neo-Hookean, Mooney model and experimental test. The physical characteristic of EVA foam was also evaluated by scanning electron microscopy (SEM). The results show that Blatz-Ko and Neo-Hookean model can fit the curve at 5% and 8% strain, respectively. The Mooney model can fit the curve at 50% strain. The modulus of rigidity evaluated from Mooney model is 0.081 4 ± 0.002 7 MPa. The structure of EVA foam from SEM image shows that EVA structure is a closed cell with homogeneous porous structure. From the result, it is found that Mooney model can adjust the data better than other models. This model can be applied for mechanical response prediction of EVA foam and also for reference value in engineering application.

Keywords

hyperelastic models / modulus of rigidity / EVA foam / curve fitting method / strain energy function / uniaxial compressive testing

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