ELASTIC POTENTIAL FUNCTION OF SLIGHTLY COMPRESSIBLE RUBBER-LIKE MATERIALS

In order to obtain an analytical expression for the stored energy function W of slightly compressible rubberlike materials, two recent results are used to obtain a unified expression which is presented in some detail. Also, a straightforward transformation technique is formulated such that one can easily relate the stress-strain relation in terms of modified stretch ratio lambda //i to the new invariants GAMMA //i. Thus, by a combination of equations and the transformation technique, one may readily determine the elastic strain energy function of slightly compressible materials from careful measurements of the volume change in multiaxial deformations. 9 refs.