Computational modeling and multiscale homogenization of short fiber composites considering complex microstructure and imperfect interfaces

• Published in: Composite structures 2023-02, Vol.306, p.116592, Article 116592
• Main Authors: Shu, Wenya, Stanciulescu, Ilinca
• Format: Article
• Language: English
• Subjects: Cohesive zone modeling; Multiscale homogenization; Orientation reconstruction; Representative volume element (RVE); Short fiber composites
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2022.116592

This paper presents a computational framework and a sequential multiscale homogenization strategy for the characterization of short fiber reinforced composites (SFRCs), followed by a study on the influence of imperfect interfaces and complex microstructures on the effective properties of the composites. The computational homogenization is performed by the cohesive finite element modeling of the representative volume element (RVE) with periodic boundary conditions. A novel method based on the iso-probability partition of a unit sphere surface, is proposed to reconstruct the fiber orientation state with a small number of fibers. The generated representativeness of the geometry is discretized by a two-stage algorithm, establishing a finite element model with the fiber/matrix interfaces represented by the cohesive zone elements. A multiscale homogenization strategy is also introduced to analytically approximate the elastic properties of the SFRCs with complex microstructure and interface defects. An extensive comparison between the computational and analytical predictions and the validations with the experimental data demonstrated the accuracy of the proposed approaches in the characterizations of SFRCs. Additionally, the influence of imperfect interfaces on the overall elastic properties was systematically evaluated by studying material systems with varying microstructures. •Proposed an efficient ODF-based fiber orientation reconstruction algorithm.•Developed RVEs with fiber misalignment and cohesive fiber/matrix interfaces.•Introduced a multiscale homogenization method for fast characterization.•Revealed the influence of interface on SFRCs with varying microstructures.