Variational phase-field formulation of non-linear ductile fracture

authored by: M. Dittmann, F. Aldakheel, J. Schulte, P. Wriggers, C. Hesch
Abstract: Variationally consistent phase-field methods have been well established in the recent decade. A wide range of applications to brittle and ductile fracture problems could already demonstrate the ability to predict complex crack patterns in three-dimensional geometries. However, current phase-field models to ductile fracture are not formulated for both, material and geometrical non-linearities. In this contribution we present a computational framework to account for three-dimensional fracture in ductile solids undergoing large elastic and plastic deformations. The proposed model is based on a triple multiplicative decomposition of the deformation gradient and an exponential update scheme for the return map in the time discrete setting. This increases the accuracy on the entire range of the ductile material behavior encompassing elastoplasticity, hardening, necking, crack initiation and propagation. The accuracy and convergence properties are further improved by the application of a higher order phase-field regularization and a gradient enhanced plasticity model. To account for the ductile behavior at fracture, a model of the critical fracture energy density depending on the equivalent plastic strain is proposed and validated by experimental data.
Organisation(s): Institute of Continuum Mechanics
External Organisation(s): University of Siegen
Type: Article
Journal: Computer Methods in Applied Mechanics and Engineering
Volume: 342
Pages: 71-94
No. of pages: 24
ISSN: 0045-7825
Publication date: 01.12.2018
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Computational Mechanics, Mechanics of Materials, Mechanical Engineering, General Physics and Astronomy, Computer Science Applications
Electronic version(s): https://doi.org/10.1016/j.cma.2018.07.029 (Access: Closed)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{d805c76a90b34424bdc96a9e9e23d3d9,
title = "Variational phase-field formulation of non-linear ductile fracture",
abstract = "Variationally consistent phase-field methods have been well established in the recent decade. A wide range of applications to brittle and ductile fracture problems could already demonstrate the ability to predict complex crack patterns in three-dimensional geometries. However, current phase-field models to ductile fracture are not formulated for both, material and geometrical non-linearities. In this contribution we present a computational framework to account for three-dimensional fracture in ductile solids undergoing large elastic and plastic deformations. The proposed model is based on a triple multiplicative decomposition of the deformation gradient and an exponential update scheme for the return map in the time discrete setting. This increases the accuracy on the entire range of the ductile material behavior encompassing elastoplasticity, hardening, necking, crack initiation and propagation. The accuracy and convergence properties are further improved by the application of a higher order phase-field regularization and a gradient enhanced plasticity model. To account for the ductile behavior at fracture, a model of the critical fracture energy density depending on the equivalent plastic strain is proposed and validated by experimental data.",
keywords = "Ductile fracture, Finite deformations, Gradient plasticity, Higher order phase-field approach, Isogeometric analysis",
author = "M. Dittmann and F. Aldakheel and J. Schulte and P. Wriggers and C. Hesch",
year = "2018",
month = dec,
day = "1",
doi = "10.1016/j.cma.2018.07.029",
language = "English",
volume = "342",
pages = "71--94",
journal = "Computer Methods in Applied Mechanics and Engineering",
issn = "0045-7825",
publisher = "Elsevier",
}