Adhesively bonded single-lap joints (SLJ) are widely used in composite structures. They are known to be sensitive to low-velocity impact damage, which may significantly reduce residual strength. While this behavior has been investigated for thermoset-based composite joints, corresponding studies on carbon fiber reinforced high-performance thermoplastic (CF-TP) adhesive joints remain scarce. In particular, the influence of different impact-induced damage characteristics on joint strength is not yet fully understood. In this study, adhesively bonded SLJ with CF-TP adherends were subjected to low-velocity impact, followed by non-destructive damage characterization. Six categories of impact damage were identified, ranging from localized to widespread delamination. The residual strength, deformation behavior and fracture pattern characteristics were systematically analyzed and complemented by finite element simulations. Furthermore, a generic numerical damage study was conducted to isolate effects of delamination size and through-thickness position. Results indicate a clear distinction between damage-tolerant and damage-critical states. Localized delamination does not lead to significant reduction in residual strength. However, widespread delamination causes a pronounced reduction. Numerical results indicate that delamination-induced stress redistribution in the adhesive layer governs joint failure. The numerical study further demonstrates that the position of delamination relative to the adhesive layer is more critical than the size of the delamination.     «

Adhesively bonded single-lap joints (SLJ) are widely used in composite structures. They are known to be sensitive to low-velocity impact damage, which may significantly reduce residual strength. While this behavior has been investigated for thermoset-based composite joints, corresponding studies on carbon fiber reinforced high-performance thermoplastic (CF-TP) adhesive joints remain scarce. In particular, the influence of different impact-induced damage characteristics on joint strength is not y...     »