2024-03-29T05:51:20Zhttps://riubu.ubu.es/oai/requestoai:riubu.ubu.es:10259/56692023-04-30T22:42:12Zcom_10259_4201com_10259_5086com_10259_2604col_10259_4505
Díaz Portugal, Andrés
Cuesta Segura, Isidoro Iván
Rodríguez, C.
Alegre Calderón, Jesús Manuel
2021-03-25T09:59:59Z
2021-03-25T09:59:59Z
2021-04
0167-8442
http://hdl.handle.net/10259/5669
10.1016/j.tafmec.2020.102879
Hydrogen assisted fracture near welds is the result of a combination of microstructural changes and the accumulation of hydrogen. With the aim of predicting local hydrogen concentrations, hydrogen redistribution near a crack tip is simulated using a Boundary Layer approach and diffusion modelling is modified by trapping phenomena. The simulated non-homogeneous geometry includes layers that reproduce weld metal, heat affected zones and base metal of a 2.25Cr-1Mo steel; mechanical and diffusion properties have been extracted from references. The hydrogen transport model here considered involves a stress dependency that affects local concentrations; thus, the possible interaction between constraint effects associated to a graded material with hydrogen entry and transport is studied. Results show that the constraint effect is not significative for the loading and for the widths assigned to the weld and the heat affected zones (2.5 to 5 mm); however, for the HAZ-centred crack, a higher hydrostatic peak and the corresponding increase in lattice hydrogen are found. A two-type trapping process is also simulated to reproduce simultaneously the effect of dislocation trapping and microstructure delayed diffusion. Hydrogen is weakly trapped in dislocations and it is added to the lattice concentration to obtain a measure of diffusible hydrogen near a crack tip while effective diffusivity is strongly reduced by deeply trapped hydrogen. Differences between environmental or internal hydrogen sources are expected to be more accurately captured because stress-dependent boundary conditions have been implemented for hydrogen uptake.
Ministry of Science, Innovation and Universities of Spain through gran RTI2018-096070-B-C33
application/pdf
eng
Elsevier
Theoretical and Applied Fracture Mechanics. 2021, V. 112, 102879
https://doi.org/10.1016/j.tafmec.2020.102879
info:eu-repo/grantAgreement/MICINN/RTI2018-096070-B-C33
Attribution-NonCommercial-NoDerivatives 4.0 Internacional
http://creativecommons.org/licenses/by-nc-nd/4.0/
info:eu-repo/semantics/openAccess
Hydrogen embrittlement
Fracture Mechanics
Hydrogen diffusion
Welding
Finite Element simulation
Resistencia de materiales
Strength of materials
Influence of non-homogeneous microstructure on hydrogen diffusion and trapping simulations near a crack tip in a welded joint
info:eu-repo/semantics/article
info:eu-repo/semantics/acceptedVersion
Theoretical and Applied Fracture Mechanics
112
102879