Modelling inelastic stress–strain phenomena and a scheme for efficient experimental characterization

A set of four representative elastomers, natural rubber (NR) and styrene-butadiene rubber (SBR), with and without filler, have been characterised. The experimental scheme was devised to cover phenomena of most practical interest, including Mullins and Fletcher-Gent (or Payne) effects, as well as quantifying both the extent of strain-induced anisotropy and the significance of time dependence. The parameters of a model of rubber phenomenology (“MORPH”) have been fitted to the experimental data. The application of the model to dynamic properties (including the Fletcher-Gent effect) are explored in this paper. The objective is to combine the established good overall treatment of the large strain behaviour of filled rubber with a capability of modelling correctly the response to small cyclic deformations. The limitations of the model are discussed in the light of the experimental results, together with options for modifying the model. The effect of static prestrain, or occasional large strain events, on the quality of vibration isolation could then be addressed by such a model.