A phenomenological constitutive model for the viscoelastic deformation of elastomers

Abstract

This study proposes a one-dimensional constitutive model for elastomeric materials based on recent observations regarding the separation of elastic and viscous contributions in uniaxial cyclic tensile experiments on EPDM rubber. The focus is on capturing the changes in constitutive behavior and energy dissipation associated with the Mullins effect. In the model, this is achieved through the evolution of both permanent set and hyperelastic parameters of an Edwards-Vilgis function to account for the Mullins effect, and with a viscosity associated with the effective stretch rate of the network to describe the non-linear flow stress. The simulations are able to reproduce the observed constitutive response and its change with increasing levels of pre-deformation. The model is less able to accurately reproduce the virgin loading response, which is achieved via extrapolation to zero pre-strain. However, for practical purposes, where scragging of elastomeric products is the norm, the model is able to predict the cyclic response and the dissipated energy, and their change with different scragging levels in good agreement with experimental data.

ANSYS Simulation of the Thermomechanical Behavior of a Large-Sized Composite Mandrel with Consideration of Viscoelasticity

“…Scientists are proposing new models based on classical models to describe the behavior of new materials, such as smart materials. In a number of works, new constitutive relations are formulated that take into account the contribution of thermal relaxation and phase transitions to the history of deformation [25][26][27]. An inevitable consequence of the refinement of the description of properties in such models is the complexity of their application in solving real technological problems, associated, first of all, with significant computational costs.…”

Mechanics of soft polymeric materials using a fractal viscoelastic model

“…Phenomenological approaches have been undertaken for predicting the elastoviscoplastic (Rajan et al 2019) and buckling (Babu et al 2019) mechanics of hydrogels. Another phenomenological constitutive model for predicting the mechanics of viscoelastic deformation in elastomers has been proposed (Annarasa et al 2020). A viscoelastic model has been developed to predict the mechanics of hydrogels using deviatoric stress and viscous over-stress, by using a modified Kelvin-Voigt model (Bacca and McMeeking 2017).…”