PSI - Issue 41

Jesús Toribio et al. / Procedia Structural Integrity 41 (2022) 728–735 Jesús Toribio / Procedia Structural Integrity 00 (2022) 000–000

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6. Conclusions 1. A method was proposed to estimate the crack tip strain rate (CTSR) or local strain rate at the crack tip , on the basis of stress distributions in its vicinity. 2. The procedure is fully analytical, and thus presents clear advantages of generality and simplicity over traditional numerical methods applied to particular cases. 3. The estimated values of the CTSR were applied to the modelling of slow strain rate tests on precracked samples under hydrogen embrittlement environmental conditions. 4. Model results with cracked samples agree fairly well with previous modelling of hydrogen embrittlement phenomena on notched samples of different geometries. 5. These results confirm the key role of the CTSR in hydrogen embrittlement phenomena and processes in the presence of stress (or strain) concentrations. 6. The level of triaxiality (constraint) associated with the cracked or notched sample influences the kinematic results in hydrogen assisted fracture. 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