ABSTRACT
The present study deals with the predicted temperature evolution of rubber under cyclic loading at constant ambient temperature. The heat sources produced or absorbed by the stretched material are obtained from the loading conditions by using the framework of the continuum thermodynamics (Lemaitre & Chaboche 1990; Maugin 1999) with an isotropic thermo-hyper-elastic behaviour. The heat sources considered here are only due to the entropic coupling. The temperature variations are then
1 INTRODUCTION
Elastomers are polymeric materials that can undergo large deformations without breaking owing to the ability of their constituent polymeric chains to rotate about the chain bonds. They are used in many application fields as mechanical engineering, automotive engineering and aerospace engineering due to their high elasticity, high damping and high elongation at failure. However, many phenomena involved in the deformation process of such materials are still not really understood. One can cite non-exhaustively phenomena such as: stress softening referred to as the Mullins effect (Mullins 1948; Marckmann et al. 2002; Diani et al. 2009) in the literature, the Payne (or Fletcher-Gent) effect (Fletcher & Gent 1953; Payne 1962; Barick & Tripathy 2010; Barmouz et al. 2011), the cavitation (Stringfellow & Abeyaratne 1989; Le Cam & Toussaint 2008; Le Cam & Tousaint 2009) and the stress-induced crystallization (Toki et al. 2000, Toki et al. 2002; Trabelsi et al. 2002; Trabelsi et al. 2003; Huneau 2011). Classically, rubber-like elasticity is described as an entropic effect, which leads to a heat production (absorption) during loading (unloading). The first experimental observations
deduced from the heat sources by solving the heat diffusion equation. For the sake of simplicity of processing (in order to avoid full 3D calculations), applications are performed here with homogeneous deformation fields. This hypothesis does not alter the conclusions of the study and enables us to focus on the specificities of the thermal response of rubber.
