Parameters evaluation of three-element solid model for viscoelastic materials by indentation test

Abstract

Mechanical tests are necessary to evaluate the deformation behavior of various materials. In particular, it is require that low- or non-destructive evaluation methods such as in-line inspection, which are employed in industries where less time and effort method is required. In this study, a spherical indentation method is developed to evaluate the mechanical properties of viscoelastic materials. The indentation method which can measure the Young's modulus of soft elastomer with finite thickness is applied to evaluate soft viscoelastic materials. The three-element solid model which can express strain rate dependency and stress relaxation is adopted as the constitutive model of the materials. The viscoelastic parameters of the three-element solid model are evaluated by defining the deformation resistance modulus, which depends on the indentation method. The applicability of the method is verified by comparing the parameters evaluated by both tensile and indentation tests. The results show that viscoelasticity can be evaluated as well as elasticity by the proposed low-destructive spherical indentation method. © 2011 The Society of Materials Science, Japan.