A simple interpolation-based approach towards the development of an accurate phenomenological constitutive relation for isotropic hyperelastic materials

Soft materials such as rubber and hydrogels are commonly used in industry for their excellent hyperelastic behaviour. There various types of constitutive models soft materials, phenomenological very popular finite element method (FEM) simulations. However, it is not easy to construct a model that can precisely predict the complex behaviours materials. In this paper, we suggest strain energy density functions should be expressed ordered principal stretches, which have more flexible expressions capable matching experimental curves. Moreover, feasible region small, simple experiments, uniaxial tension/compression hydrostatic tests, on its boundaries. Therefore, easily constructed by interpolation curves, does need initial guessing form function most existing do. The proposed perfectly consistent with available curves interpolation. It interesting find incompressible 3D relation obtained from single stress–strain curve (from compression tension) via interpolation, other reasonably well. To further improve accuracy, additional experiments