Characterization of the Effect of Notch Bluntness on Hydrogen Embrittlement and Fracture Behavior Using FE Analyses

This paper introduces a method to characterize the effect of notch bluntness on hydrogen embrittlement for high strength structural steel, FeE 690T, C(T) specimens. Hydrogen concentration depending on notch radius is assessed via finite element (FE) hydrogen diffusion analysis already developed and validated by the authors. Reduction in fracture toughness, K_IC or J_IC, due to hydrogen embrittlement is evaluated by means of a coupled hydrogen diffusion-ductile damage analysis. The ductile damage simulation used in this study is based on the model known as ‘stress-modified fracture strain model’. Tensile properties and fracture strains are modified according to the level of hydrogen concentration in the simulation and its effect on the fracture behavior of the specimen is simulated for different notch radii.