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

verfasst von
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.

Organisationseinheit(en)
Institut für Statik und Dynamik
Typ
Aufsatz in Konferenzband
Band
93
Publikationsdatum
2010
Publikationsstatus
Veröffentlicht
Peer-reviewed
Ja
ASJC Scopus Sachgebiete
Environmental engineering, Tief- und Ingenieurbau, Theoretische Informatik und Mathematik, Artificial intelligence
Elektronische Version(en)
https://doi.org/doi:10.4203/ccp.93.272 (Zugang: Unbekannt)