Damage quantification in an aluminium-CFRP composite structure using guided wave wavenumber mapping: Comparison of instantaneous and local wavenumber analyses

Composite-overwrapped pressure vessels (COPV) are increasingly used in the transportation industry due to their high strength mass ratio. Throughout years, various designs were developed and found applications. Currently, there five designs, which can be subdivided into two main categories - with a load-sharing metal liner non-load-sharing plastic liner. The damage mechanism defining lifetime of first type is fatigue liner, whereas for second it composite overwrap. Nevertheless, one may drastically reduce COPV impact-induced damage. Therefore, this barely visible needs assessed non-destructive way decide whether vessel further or has put out service. One possible methods based on ultrasonic waves. In contribution, both conventional testing (UT) by high-frequency bulk waves wavenumber mapping low frequency guided evaluate impact Wavenumber techniques benchmarked simulated aluminium panel then applied experimental measurements acquired delaminated aluminium-CFRP plate corresponds structure analysis data obtained from propagating an performed. All approaches show similar performance terms quantification size depths while being numerical data. deliver accurate estimate in-plane large delamination at interface but only rough its depth. Moreover, none study quantify every between CFRP plies caused impact, case UT. This solved using higher frequencies (shorter wavelengths) more advanced signal processing techniques. all, concluded that imaging complex fibre-reinforced composites not straightforward stays challenging task.