The objective of the testing described herein is to define and to satisfy the input requirements of mathematical material models that exist in structural, non-linear finite element analysis software.

The testing of elastomers for the purpose of defining material models is often misunderstood. The appropriate experiments are not yet clearly defined by national or international standards organizations. This difficulty derives from the complex mathematical models that are required to define the nonlinear and the nearly incompressible attributes of elastomers.

Most of these models are referred to as hyperelastic material models. It is beyond the scope of this article to discuss the details of particular hyperelastic material models. However, most models share common test data input requirements. In general, stress and strain data sets developed by stretching the elastomer in several modes of deformation are required and “fitted” to sufficiently define the variables in the material models.

Reprinted with Permission from Kurt Miller - www.axelproducts.com