Confined compression: A stable homogeneous deformation for constitutive characterization

An experimental configuration is described in which the complete state of stress and strain in the specimen are determined through direct experimental measurement, without a priori constitutive assumptions with regard to the material behavior. Moreover, the control of the deformations is such that the deformations are always stable. Design considerations in implementing such an experimental configuration and applications to the investigation of the multiaxial constitutive behavior in materials are also described. An example of the implementation is demonstrated using Al 6061-T6 alloy.