Data-driven microstructure-generator for high-fidelity analyses of unidirectional composite laminates
Please login to view abstract download link
Nowadays, micromechanical finite element analyses are a well-established technique to investigate the early-stage damage mechanisms of composite materials and to predict their homogenized mechanical properties. State-of-the-art high-fidelity simulations typically include consistent constitutive equations for the fibres and the matrix, the presence of the interfaces and, lately, the effect of voids and of the curing process [1]. Less emphasis is typically given to the fibre distribution itself [2]. In this work, the focus is given to the definition of a data-driven workflow for the generation of statistically equivalent fibre distributions for the simulation of composite systems. Unidirectional composites produced with different manufacturing processes are investigated. More in detail, a hand-layup thermoset material cured in the autoclave is compared with a thermoplastic system consolidated in the hot press. Micrographs of the cross-section are analysed and the positions of fibres identified via digital-image analyses. Local and global statistical spatial descriptors including the nearest-neighbour distribution and the nearest-neighbour-orientations are then used for the fiber spatial distribution characterization. Statistically equivalent RVEs are then generated using the obtained descriptors and their mechanical response under different loading conditions is investigated. A set of linear elastic analyses is used to identify correlations between the fibre distribution and the resulting composite elastic properties. The matrix is then endowed with an elasto-plastic damageable model while the cohesive zone model technique is used to reproduce the failure in the fibre/matrix interface. The final results point out how different manufacturing processes induce a directionality in the microstructure distributions whose effect on the material degradation can not be neglected. Acknowledgements: The author FD would like to acknowledge the financial support of the FCT via the project UIDP/50022/2020 (LAETA Programatic Funding). REFERENCES [1] F. Danzi and D. Fanteria and E. Panettieri and M.C. Mancino. A numerical micro-mechanical study on damage induced by the curing process in carbon/epoxy unidirectional material. Comp. Struct., Vol. 210, 2019. [2] F. Husseini and J. Pineda and E. Stapleton. Generation of artificial 2-D fiber reinforced composite microstructures with statistically equivalent features. Comp. Part A., Vol. 164, 2023.