Non-linear viscoelastic behavior of filled elastomers

The analysis of the results of experimental studies of relaxation properties of rubber at room temperature under the conditions of tension and compression at different strain levels is carried out. For the description of viscohyperelastic deformation of filled elastomers, the constitutive relations are used that are the generalization of non-linear elasticity and linear viscoelasticity Boltzmann–Volterra. The method for the determination of interrelated hyperelastic and reological characteristics of deformation is proposed. On the base of experimental data, the dependence of relaxation properties of elastomer on the strain level is discovered and the approach to the description of this dependence based on the constitutive relations of non-linear endochronic theory of aging viscoelastic materials is proposed. The finite element numerical simulation of an experiment under conditions of the confined compression of flat cylindrical specimen and subsequent relaxation is performed. Sufficient correspondence between the calculated values of axial load and the results of experimental study is demonstrated.