A novel ‘integrated’ approach coupling image correlation and elastic displacement field identification provides a powerful and accurate tool to evaluate mode I and II stress intensity factors. This technique is applied to silicon carbide subjected to a sandwiched three-point bend test, using digital pictures obtained in optical microscopy where the pixel physical scale is about 2 μm. A crack whose maximum opening is 500 nm can be detected and its geometry identified. The toughness is determined well within a 10%uncertainty.
Une nouvelle technique de corrélation d'images, dite « intégrée », est proposée. Couplée à l'identification d'un champ de déplacement d'un milieu élastique, elle permet de déterminer les facteurs d'intensité des contraintes en modes I et II. Cette technique est appliquée à un carbure de silicium lors d'un essai de préfissuration, en exploitant des images de microscopie optique dont la taille physique du pixel vaut 2 μm. Une fissure dont l'ouverture maximale est d'ordre 500 nm est identifiée et sa géométrie estimée. Les facteurs d'intensité des contraintes sont déterminés avec une incertitude bien inférieure à 10%.
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Mots-clés : Rupture, Photomécanique, Matériau fragile, Ténacité
François Hild  1 ; Stéphane Roux  2
@article{CRMECA_2006__334_1_8_0,
author = {Fran\c{c}ois Hild and St\'ephane Roux},
title = {Measuring stress intensity factors with a camera: {Integrated} digital image correlation {(I-DIC)}},
journal = {Comptes Rendus. M\'ecanique},
pages = {8--12},
year = {2006},
publisher = {Elsevier},
volume = {334},
number = {1},
doi = {10.1016/j.crme.2005.11.002},
language = {en},
}
TY - JOUR AU - François Hild AU - Stéphane Roux TI - Measuring stress intensity factors with a camera: Integrated digital image correlation (I-DIC) JO - Comptes Rendus. Mécanique PY - 2006 SP - 8 EP - 12 VL - 334 IS - 1 PB - Elsevier DO - 10.1016/j.crme.2005.11.002 LA - en ID - CRMECA_2006__334_1_8_0 ER -
François Hild; Stéphane Roux. Measuring stress intensity factors with a camera: Integrated digital image correlation (I-DIC). Comptes Rendus. Mécanique, Volume 334 (2006) no. 1, pp. 8-12. doi: 10.1016/j.crme.2005.11.002
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