Single overloads FCG modeling considering damage accumulation

Abstract

In this study, Fatigue Crack Growth (FCG) in a CT specimen, submitted to single overloads, is predicted by a node release numerical model, which considers the plastic strain to be the main FCG driving force. The Gauss-Tvergaard-Needleman (GTN) damage model was implemented to account for the, inevitable, growth and nucleation of microvoids in the occurrence of high levels of plastic strain. Crack closure shown to be a crucial mechanism influencing the differences between both models, as well as it explains the effects of the overloads on the FCG rate.