We are pleased to highlight a recent scientific publication supported by the UPBEAT project and co-authored by Sérgio Costa (GKN Aerospace). The study presents a high-fidelity micromechanical modelling framework that incorporates realistic three-dimensional (3D) fibre waviness and waviness-induced residual stresses in unidirectional (UD) carbon-fibre composites.
Why is this important? Manufacturing-induced defects, particularly fibre waviness, can significantly reduce the compressive strength of composite materials used in aerospace and other high-performance applications. Existing modelling approaches often represent these defects using idealised two-dimensional descriptions, limiting their ability to accurately predict real structural behaviour. Using fibre trajectories derived from X-ray computed tomography data, the researchers developed detailed finite element models that capture the inherently 3D nature of fibre misalignment. The study demonstrates that realistic 3D fibre waviness can have a significantly greater impact on compressive strength than simplified 2D representations, highlighting the importance of accurately characterising manufacturing defects. This work supports UPBEAT’s goal of predicting the influence on the load bearing of manufacturing-induced defects in advanced composite structures. A detailed micromechanical models provide input to ply level material models necessary for to the development of safer, lighter and more efficient composite components for future aerospace applications.
Read the full paper for more details on the modelling framework and findings. https://doi.org/10.1016/j.compositesa.2026.109811
