Ductile rupture of aluminum sheet materials
Keywords:
Aluminum 2024, sheet, ductile rupture, Rousselier modeZ, cohesive zone modelAbstract
This study deals with ductile tearing of Aluminum 2024 sheets. Tensile tests were conducted on smooth and notched specimens. They show that the plastic behavior is anisotropie. The crack path is slanted on moderately notched specimens whereas a normal to slant fracture transition is observed on severe/y notched samples. The damage behavior is mode led using the Rousselier mode/ extended to account for plastic anisotropy. ft is shawn that the stress triaxiality can reach values up to 1.6. This shows, rogether with the slanted crack path, the importance of a 3D modeling. As the se calculations require a large computational capacity, a relative/y coarse mesh was used so thal the load is overestimated. The experimental load could be reproduced changing the material parameters; in this case normal fracture is obtained. A finer mesh should be used to obtain simultaneously the correct crack path and load. To mode/ cracking in large structures, a 2D plane stress cohesive zone mode/ is used.
Downloads
References
(BES 97) BESSON J ., FOERCH R., "Large scale object-oriented finite element code design",
Computer Methods in Applied Mechanics and Engineering, vol. 142, 1997, p. 165-187.
[BES 98) BESSON J., FOERCH R., "Application of object-oriented programming techniques
to the finite element method. Part 1- General concepts", Revue européenne des éléments
finis, vol. 7, num. 5, 1998, p. 535-566.
(GRA 00] GRANGE M., BESSON J ., ANDRIEU E., "An anisotropie Gurson mode! to represent
the ductile rupture of hydrided Zircaloy-4 sheets", !nt. J. Fracture, vol. 105, num. 3, 2000,
p. 273-293.
[GUL 99) GULLERUD A., DODDS R., HAMPTON R., DAWICKE D., "Three dimensional
modeling of ductile crack growth in thin sheet metals: computational aspects and
validation", Eng. Fracture Mechanics, vol. 63, 1999, p. 347-373.
[GUL 00) GULLERUD A., GAO X., DODDS JR R., HAJ-ALI R., "Simulation of ductile crack
growth using computational cells: numerical aspects", Eng. Fracture Mechanics, vol. 66,
, p. 65-92.
[HER 98] HERMANN G., Déchirure ductile de tôles minces d'un alliage Aluminium-Cuivre,
report , 1998, Pechiney CRY.
[LAD 80) LA DE VÈZE P., Sur la théorie de la plasticité en grandes déformations, report, 1980,
Rapport interne No. 9, LMT, ENS Cachan.
[LIU 94) LIU Y., MURAKAMI S., KANAGAWA Y., "Mesh-dependence and stress singularity
in finite element analysis of creep crack growth by continuum damage mechanics
approach", Eur. J. Mech, A/Sa/ids, vol. 13, num. 3, 1994, p. 395-417.
[NEE 90] NEEDLEMAN A., "An analysis of tensile decohesion along an interface", J. Mech.
Phys. Sa/ids, vol. 38, 1990, p. 289-324.
[NEE 92) NEEDLEMAN A., "An analysis of decohesion along an imperfect interface", /nt. J.
Fracture, vol. 40, 1992, p. 1377-1397.
[O'D 92) 0' DOWD N ., SHIH C., "Family of crack-tip fields characterized by a triaxiality
parameter-II. Fracture Applications", J. Mech. Phys. Sa/ids, vol. 40, num. 8, 1992, p. 939-
[RIC 68] RICE J., "A path independent integral and the approximate analysis of strain
concentration by notched and cracks", J. Appl. Mech., vol. 35, 1968, p. 379.
[ROU 87] RoussELIER G., "Ductile fracture models and their potential in local approach of
fracture", Nuclear Engineering and Design, vol. 105, 1987, p. 97-111.
[RUD 75] RUDNICKI J., RICE 1., "Conditions for the localization of deformation in pressuresensitive
dilatant materials", J. Mech. Phys. Sol., vol. 23, 1975, p. 371-394.
[SIE 99) SIEGMUND T., BROCKS W., "Prediction of the work of separation and implications
to modelling", !nt. J. Frac., vol. 99, 1999, p. 97-116.
[SIM 85] SIMO 1., TAYLOR R., "Consistent tangent operators for rate-independent
elastoplasticity", Computer Methods in Applied Mechanics and Engineering, vol. 48, 1985,
p. 101-118.
[STE 98] STEGLICH D., BROCKS W., "Micromechanical modelling of damage and fracture
of ductile materials", Fatigue Frac!. Engng Mater. Struct., vol. 21, 1998, p. 1175-1188.
[SUN 88] SUN D., SIEGELE D., Yoss B., SCHMITT W., "Application of local damage
models to the numerical analysis of ductile rupture", Fatigue and Fracture of Engineering
Materials and Structures, vol. 12, 1988, p. 201-212.
[TUR 92) TURNER C., "A re-assessment of ductile tearing resistance. Part I: The geometry
dependence of J-R curves in fully plastic bending. Part Il: Energy dissipation rate and
associated R-curves in fully plastic bending.", Fracture behavior and design ofmaterials
and structures, ECF 8, 1992, p. 933-968.
