Mode I Interlaminar Fracture Toughness Characterisation of Carbon Fibre Reinforced Thermoplastic Composites

Delamination has always been regarded as one of the most critical failures in laminated composites. The growing interest in a more rapid, out-of-autoclave (OOA) manufacturing techniques for automotive applications such as compression moulding and thermoforming has prompted the engineering community to further investigate and understand the delamination resistance of carbon fibre reinforced thermoplastic (CFRTP) composites over the more conventional carbon fibre reinforced thermosetting (CFRTS) counterparts. In this study, the mode I (opening) interlaminar fracture toughness of two non-crimp fabric (NCF) biaxial (0/90º) carbon/thermoplastic composite systems with fibre volume fraction (FVF) of 50%; T700/polyamide 6.6 and T700/polyphenylene sulphide have been characterised. The mode I delamination resistance, for both materials was determined using the double cantilever beam (DCB) specimen. Following the experimental results and data reduction, the Mode I interlaminar fracture toughness were compared. Fractographic analysis was conducted using a scanning electron microscope (SEM) to characterise the microstructure of the failed specimens.