Quantification of Crack Length and Thickness Effects on J-R Curves by Ductile Damage Models

In this paper, the applicability of local approach is examined for SA515 Gr.60 nuclear steel through a series of finite element analyses incorporating modified GTN and Rousselier models as well as fracture toughness tests. To achieve the goal, fracture toughness test data of standard compact tension (CT) specimens are used for calibration of micro-mechanical parameters. Then, from finite element analyses employing the calibrated parameters, fracture resistance (J-R) curves of CT specimens with different crack length to width ratio, with different thickness and with/without 20% side-grooves are predicted. Finally, suitability of the numerically estimated J-R curves was verified by comparison with the corresponding experimental J-R curves.