MODIFICATION OF THE LEMAITRE DAMAGE MODEL BY A LOCAL MULTIAXIAL STRESS STATE FUNCTION

Abstract

A modification of the Lemaitre damage model is proposed based on the introduction of a function sensitive to the Lode parameter. The modified model is imported into the ANSYS software as a dynamically linked custom tag library. The model takes into account isotropic hardening based on the exponential Voice model and kinematic hardening based on the Armstrong–Frederick model. Limit state curves are obtained by numerical finite element analysis for three types of experimental cylindrical specimens: a compression specimen under additional external pressure, a circular-notch specimen under uniaxial tension, and a hollow cylindrical specimen under combined tension, torsion, and internal pressure. The advantages and disadvantages of the proposed model are considered. Recommendations are given for choosing model parameters to predict limit states under multiaxial loading.