A finite strain, finite band method for modeling ductile fracture

• Published in: International journal of plasticity 2012, Vol.28 (1), p.53-69
• Main Authors: Huespe, A.E., Needleman, A., Oliver, J., Sánchez, P.J.
• Format: Article
• Language: English
• Subjects: Deformation; Discontinuity; Ductile fracture; Ductile fracture modeling; Embedded weak discontinuities; Exact sciences and technology; Finite element methods; Finite strain plasticity; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Inelasticity (thermoplasticity, viscoplasticity...); INT; Mathematical analysis; Mathematical models; Physics; Plasticity; Regularization; Solid mechanics; Structural and continuum mechanics
• ISSN: 0749-6419; 1879-2154
• DOI: 10.1016/j.ijplas.2011.05.010

► The method provides a framework for modeling the transition from a weak discontinuity to a strong discontinuity. ► An embedded weak discontinuity is introduced when the loss of ellipticity condition is met. ► One main application is to ductile fracture modeling, as also, to other circumstances. ► Examples show that rather complex failure modes, such as a cup-cone fracture, can be represented. We present a finite deformation generalization of the finite thickness embedded discontinuity formulation presented in our previous paper [A.E. Huespe, A. Needleman, J. Oliver, P.J. Sánchez, A finite thickness band method for ductile fracture analysis, Int. J. Plasticity 25 (2009) 2349–2365]. In this framework the transition from a weak discontinuity to a strong discontinuity can occur using a single constitutive relation which is of importance in a range of applications, in particular ductile fracture, where localization typically precedes the creation of new free surface. An embedded weak discontinuity is introduced when the loss of ellipticity condition is met. The resulting localized deformation band is given a specified thickness which introduces a length scale thus providing a regularization of the post-localization response. The methodology is illustrated through several example problems emphasizing finite deformation effects including the development of a cup-cone failure in round bar tension.