Non-linear mechanical behaviour of carbon black reinforced elastomers: experiments and multiscale modelling

Antivibrating parts in automotives are often made of natural rubber reinforced by carbon black. This reinforcement, which comes from the filler-filler and filler-rubber interactions, leads to an increase in the elastic modulus, the tensile strength and the hysteresis. The aim of this work is to develop a micromechanical model within a generalised self-consistent scheme for filled rubber in the moderate elongation range (vertical bar epsilon vertical bar < 0.5). A complex morphological pattern, representative of the microstructure of the material, and which takes into account the occluded rubber, the bound rubber and a percolating network, is proposed and the effective elastic properties are compared with experimental results obtained in both uniaxial and oedometric compression. The influence of the specific surface of the filler is investigated, using N330 and N650 carbon blacks. The model is extended to the non-linear accommodation of the stress heterogeneities between the phases. Model predictions are compared with experimental values in compression and simple shear.