Simulating the effect of porosities on stiffness and strength of composite materials

authored by: R. Rolfes, S. Czichon, M. Vogler, E. Jansen
Abstract: Predicting the material properties of imperfect composite structures with manufacturing defects such as waviness defects or porosities remains an open challenge. Several analytical approaches exist to determine the reduction of elastic properties due to porosity. However, these analytical methods do not account for the spatial distribution and the geometry of the voids. Size, shape, location and geometric distribution of the voids significantly influence the effect of porosity defects on material properties. In the work presented, a continuum damage mechanics approach is chosen to model porosity defects. Elastic-plastic material models for epoxy resin and fiber bundles have been developed. An invariant based quadratic failure criterion is used to model damage propagation. These material models are applied to study the failure modes induced by porosity defects and to obtain reduced homogenized material parameters for the macro scale. Different failure modes, such as kink-band failure can be observed and give valuable insight on the micromechanical behavior of imperfect structures. It is shown that the fiber misalignment angle has a significant influence on strength reduction.
Organisation(s): Institute of Structural Analysis
Type: Conference contribution
Volume: 93
Publication date: 2010
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Environmental Engineering, Civil and Structural Engineering, Computational Theory and Mathematics, Artificial Intelligence
Electronic version(s): https://doi.org/doi:10.4203/ccp.93.272 (Access: Unknown)

BibTeX

@inproceedings{3f94fbb8875a47a5a02bf2a0f3845020,
title = "Simulating the effect of porosities on stiffness and strength of composite materials",
abstract = "Predicting the material properties of imperfect composite structures with manufacturing defects such as waviness defects or porosities remains an open challenge. Several analytical approaches exist to determine the reduction of elastic properties due to porosity. However, these analytical methods do not account for the spatial distribution and the geometry of the voids. Size, shape, location and geometric distribution of the voids significantly influence the effect of porosity defects on material properties. In the work presented, a continuum damage mechanics approach is chosen to model porosity defects. Elastic-plastic material models for epoxy resin and fiber bundles have been developed. An invariant based quadratic failure criterion is used to model damage propagation. These material models are applied to study the failure modes induced by porosity defects and to obtain reduced homogenized material parameters for the macro scale. Different failure modes, such as kink-band failure can be observed and give valuable insight on the micromechanical behavior of imperfect structures. It is shown that the fiber misalignment angle has a significant influence on strength reduction.",
keywords = "Composite, Finite element method, Multiscale, Porosities, Voids",
author = "R. Rolfes and S. Czichon and M. Vogler and E. Jansen",
year = "2010",
doi = "doi:10.4203/ccp.93.272",
language = "English",
isbn = "9781905088386",
volume = "93",
booktitle = "Proceedings of the 10th International Conference on Computational Structures Technology, CST 2010",
publisher = "Civil-Comp Press",
address = "United Kingdom (UK)",
note = "10th International Conference on Computational Structures Technology, CST 2010 ; Conference date: 14-09-2010 Through 17-09-2010",
}