On the description of ductile fracture in metals by the strain localization theory
Numerical simulations based on the bifurcation and imperfection versions of the strain localization theory are used in this paper to predict the failure loci of metals and applied to an advanced high strength steel subjected to proportional loading paths. The results are evaluated against the 3D unit cell analyses of Dunand and Mohr (J Mech Phys Solids 66(1):133–153, 2014. doi: 10.1016/j.jmps.2014.01.008) available in the literature. The Gurson porous plasticity model (Gurson in J Eng Mater Technol 99(1):2–15, 1977. doi: 10.1115/1.344340) is used to induce strain softening and drive the localization process. The effects of the void growth, void nucleation and void softening in shear are investigated over a large range of stress triaxialities and Lode parameters. A correlation between the imperfection and bifurcation results is established.
KeywordsLocalization Failure Bifurcation Loss of ellipticity Porous materials
O.S.H. and D.M. would like to acknowledge the financial support from the Centre for Advanced Structural Analysis (CASA) (Project No. 237885) as well as the FractAl project (Project No. 250553) funded by the Research Council of Norway and NTNU. Part of this work was performed when A.B. was a guest of the Structural Impact Laboratory at the Department of Structural Engineering at NTNU. A.B. also gratefully acknowledges the FractAl project for the financial support during his stay in Trondheim.
- Benallal A (2017) Constitutive equations for porous solids with matrix behaviour dependent on the second and third stress invariants. Int J Impact Eng. doi: 10.1016/j.ijimpeng.2017.05.004
- Di Y, Lixun C, Chen B (2016) A new fracture criterion for ductile materials based on a finite element aided testing method. Mater Sci Eng A. doi: 10.1016/j.msea.2016.06.076
- Hutchinson J, Tvergaard V (1981) Shear band formation in plane strain. doi: 10.1016/0020-7683(81)90053-6
- Jia Y, Bai Y (2016) Ductile fracture prediction for metal sheets using all-strain-based anisotropic eMMC model. Int J Mech Sci. doi: 10.1016/j.ijmecsci.2016.07.022
- Mear ME, Hutchinson JW (1985) Influence of yield surface curvature on flow localization in dilatant plasticity. doi: 10.1016/0167-6636(85)90035-3
- Needleman A, Rice JR (1978) Limits to ductility set by plastic flow localization. Mech Sheet Metal form 237–267. doi: 10.1007/978-1-4613-2880-3_10
- Rice JR (1976) The localization of plastic deformation. In: 14th International congress of theoretical and applied mechanics, pp 207–220Google Scholar