The inflation and extension of rubber tube for biaxial strain studies

Abstract

The combined extension and inflation of a thin-walled rubber tube enables homogeneous biaxial strains to be achieved up to higher strains than are obtainable with the customary flat sheet specimen, e.g. up to principal extension ratios, lambda 1 and lambda 2 of 3.3 and 5.0 respectively or more, in a typical rubber. The data obtained can be interpreted on the basis of the Valanis-Landel hypothesis for values of lambda 1 and lambda 2 up to 3.0, but for higher strains deviations from the hypothesis may occur.