106 - INTERFACIAL NORMAL RESPONSE OF CARBON AND GLASS FIBRE EPOXY COMPOSITES MONITORED VIA IN SITU HOLOTOMOGRAPHY (CompTest 2025)
First-ply failure (FPF) concerns the point at which the weakest ply in a composite laminate reaches its theoretical limit under load. This, in most cases, means that the laminate can continue to carry the load beyond FPF. Regarding damage mechanisms, FPF is often conceptually linked with the initiation of fibre-matrix interfacial (normal) debonds that evolve into off-axis cracks and, later, delamination at ply interfaces. With the continuous advancements in non-destructive testing (NDT) methods for composite structures, the notion of FPF has become increasingly important, with many applications requiring the structure never to reach FPF. That, however, comes at a cost, with excessive safety factors put in place to withstand the uncertainties associated with composite damage and failure. In this study, we shed light on the microscale damage mechanisms in FPF of composites. To achieve this, we exploit synchrotron tomography to investigate the first damage mechanism anticipated in transverse loading of composites: fibre-matrix interfacial normal debonding. Our main objectives lie in understanding the influence of fibre type and fibre packing on interfacial normal debonding and offering a state-of-the-art experimental dataset as input or validation for numerical predictions.
Pieteikuma datums
21.05.2025.
Atslēgas vārdi
Single-fibre composites, Transverse tension, Interfacial debonding, Synchrotron tomography
