Brittle cleavage fracture remains one of the major concerns for structural integrity assessment. The main characteristics of this mode of failure in relation to the stress field ahead of a crack, tip are described in the introduction. The emphasis is laid on the physical origins of scatter and the size effect observed in ferritic steels. It is shown that cleavage fracture is controlled by physical events occurring at different scales: initiation at (sub)micrometric particles, propagation across grain boundaries (10–50 microns) and final fracture at centimetric scale. The two first scales are detailed in this paper. The statistical origin of cleavage is described quantitatively from both microstructural defects and stress–strain heterogeneities due to crystalline plasticity at the grain scale. Existing models are applied to the prediction of the variation of Charpy fracture toughness with temperature.
La ruine par rupture fragile reste une des préoccupations majeures pour l'évaluation de l'intégrité mécanique des structures. Les principaux traits de l'amorçage de ce mode de rupture à la pointe d'une fissure macroscopique sont tout d'abord rappelés dans l'introduction. On met l'accent sur la dispersion inhérente à ce mode de rupture en relation avec l'origine diverse des sites d'amorçage ainsi que sur l'effet de taille. On montre que la rupture par clivage est contrôlée par des mécanismes physiques agissant à différentes échelles, celle des particules de seconde phase micrométriques et celle des grains. L'origine statistique du clivage est modélisée en prenant en compte à la fois la distribution spatiale des défauts microstructuraux et la distribution intragranulaire des contraintes et déformations. Les modèles développés sont utilisés pour prévoir la variation de la résilience avec la température.
Mots-clés : Rupture par clivage, Micromécanismes, Aciers ferritiques, Aspects statistiques, Dispersion, Modélisation multi-échelle
André Pineau 1; Benoît Tanguy 2
@article{CRPHYS_2010__11_3-4_316_0, author = {Andr\'e Pineau and Beno{\^\i}t Tanguy}, title = {Advances in cleavage fracture modelling in steels: {Micromechanical,} numerical and multiscale aspects}, journal = {Comptes Rendus. Physique}, pages = {316--325}, publisher = {Elsevier}, volume = {11}, number = {3-4}, year = {2010}, doi = {10.1016/j.crhy.2010.07.013}, language = {en}, }
TY - JOUR AU - André Pineau AU - Benoît Tanguy TI - Advances in cleavage fracture modelling in steels: Micromechanical, numerical and multiscale aspects JO - Comptes Rendus. Physique PY - 2010 SP - 316 EP - 325 VL - 11 IS - 3-4 PB - Elsevier DO - 10.1016/j.crhy.2010.07.013 LA - en ID - CRPHYS_2010__11_3-4_316_0 ER -
André Pineau; Benoît Tanguy. Advances in cleavage fracture modelling in steels: Micromechanical, numerical and multiscale aspects. Comptes Rendus. Physique, Computational metallurgy and scale transitions, Volume 11 (2010) no. 3-4, pp. 316-325. doi : 10.1016/j.crhy.2010.07.013. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2010.07.013/
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