Assessment of hyperelastic constitutive models for chopped aramid fibre-reinforced rubber composites

Abstract

Chopped aramid fibre-reinforced rubber composite (AFRC) is widely used in industry owing to its excellent characteristics. Rubber's mechanical properties vary with the addition of aramid fibres. Although hyperelastic constitutive models exist for unfilled and filled rubber with carbon black, constitutive models for AFRCs have not been investigated yet. Here, we present experimental results demonstrating the stress–strain responses of AFRC, together with the Mullins effect, under both uniaxial and equibiaxial tensile loadings. The existing classical hyperelastic constitutive models and the model proposed here were applied to AFRC. Unlike the existing model, the proposed model requires fewer variables in the energy function and permits further study of the stress-softening mechanism of AFRC. Finally, the pseudo-elastic (PE) model was applied to AFRC, revealing that the damage parameters exhibited a linear relationship with the fibre content. The PE model is, therefore, beneficial for predicting the stress softening behaviour of AFRC.