Characterising failure in textile-reinforced thermoplastic composites by electromagnetic emission measurements under medium and high velocity impact loading

The presented work focuses on failure in fibre-reinforced thermoplastic composites under medium and high velocity impact loading conditions. The investigated material is a fabric-reinforced polypropylene (PP) made of hybrid E-glass/PP yarns. Small mass impacts with velocities of 40 up to 1600 m/s are used to damage the plane specimens with a thickness of t = 2 mm. Electromagnetic and acoustic emission signals (EME and AE) are measured during the impact and signal interdependencies are elaborated. A relation can be drawn between the signal sources and the according failure modes. The examinations show, that electromagnetic emission phenomena are mainly related to fibre-matrix-debonding (FMD).