DURABILITY OF CARBON-FIBER REINFORCED-PLASTICS WITH THERMOPLASTIC MATRICES UNDER CYCLIC MECHANICAL AND CYCLIC THERMAL LOADS AT CRYOGENIC TEMPERATURES

In this paper an investigation of the fatigue behaviour of carbon fibre reinforced thermoplastics (CFRTPs) is carried out. Two commercially available composites of different interfacial strength are first examined in unidirectional lay up under tension - tension and reversed bending loads. Then cross-ply composites are tested under cyclic thermal and tension - tension load. The damage accumulation and the fracture surfaces are investigated using optical microscopy, SEM and X-ray beam analysis.