Nonproportional Multiaxial Cyclic Loading: Experiments and Constitute Modeling

Abstract

Biaxial tension compression, deformation controlled, out-of-phase cyclic tests were conducted on thin-walled circular cylindrical specimens of a low alloy carbon steel. The influence of strain amplitude and phase angle (a measure of nonproportionality of strain path) on the stress-strain loops have been studied. Material aniostropy and additional cyclic hardening due to the plastic deformation and nonproportional path are clearly observed. A constitutive model is presented which describes the material behavior under complex loading histories including cyclic deformation. The predictions of the model are compared to the experimental results, and the agreement is found to be fairly good.