Property modellingMechanical experimental characterisation and numerical modelling of an unfilled silicone rubber

In this paper, the mechanical behaviour of an unfilled silicone rubber is analysed. Firstly, silicone samples were subjected to five homogeneous tests: tensile, pure shear, compression, plane strain compression and bulge tests. During the tests, full-field measurements of the strain on the surface of deformed samples were obtained using a Digital Image Correlation technique. Results show that the Mullins effects and hysteresis, as well as strain rate sensitivity, can be considered as negligible. Results also emphasise the influence of the loading path. Then, five well-known hyperelastic models (neo-hookean, Mooney, Gent, Haines and Wilson and Ogden models) were fitted to the experimental data. Finally, a heterogeneous test was realised by stretching a silicone plate sample containing holes. Finite element simulations of this experiment have been performed with the hyperelastic models. The comparison of experimental and numerical results emphasises the importance of the choice of the hyperelastic modelling in the simulation of strain fields.