Vyas, M. and Pratley, M., "Elastomer Characterization for Digital Prototyping and Its Validation through Physical Testing," SAE Technical Paper 2017-26-0181, 2017, doi:10.4271/2017-26-0181.
There is an increased use of elastomers in the automotive industry for sealing, noise isolation, load dampening, insulation, etc., because of their key properties of elasticity and resilience. Elastomers are used in supercharger application for dampening the torsional fluctuation from the engine, to reduce noise issues. Finite element modeling of elastomers is challenging because of its non-linear behavior in different loading directions. It also undergoes very large elemental deformation (~up to 200%), which results in additional complexities in getting numerical convergence. Finally, it also exhibits viscous and elastic behavior simultaneously (viscoelastic effect) and it undergoes softening with progressive cyclic loading (Mullins effect). The present study deals with the characterization of elastomers for its modeling in commercial finite element software packages and verification of some predicted design parameters with physical testing. Test specimens comprised of elastomers are tested in different load scenarios, such as simple tension, equibiaxial tension, and pure shear at various temperatures to characterize the static behavior in both loading and unloading directions at four different strain levels. Curve fitting techniques are utilized to get the best material model that is stable at all strain levels. The component is modeled in Ansys® [1, 2] and Abaqus®  software with fitted constants, and key design parameters are predicted which are then correlated with actual test data. The methodology is currently used to qualify new design iterations, thereby reducing iterative prototype cost, testing cost and project time to develop elastomeric component.