Failure characterisation of CF/epoxy V-shape components using digital image correlation and acoustic emission analyses

Testing of V-Shape demonstrator components formed from carbon fibre epoxy composites was undertaken to
assess the failure mechanisms at the corner section (V-Shape) of a square beam structure under static and
fatigue loading configurations. Digital image correlation and acoustic emission analyses were used to determine
the time to failure, as well as the location of failure, providing additional insights for failure characterisation.
Digital image correlation was used on the surface of the specimens’ side as it analysed the displacements
and strains on the externally visible through-thickness region. Acoustic emission analyses
identified the origin and location of stress waves generated within the sample which were related to damage
events. These techniques have shown a higher sensitivity to determining the onset of damage and the time to
failure, in comparison to load drops, crosshead displacement changes, and strain gauge measurements, providing
a more conservative and accurate measurement of component failure. They have also proven successful
at determining the location of failure initiation, highlighting the added benefits of incorporating these techniques
into component analyses.