Press‐forming of continuous‐fiber‐reinforced thermoplastic composites

Abstract Process‐induced effects on thermoplastic‐based composites were investigated for laminates processed under high production rate conditions. Press‐formed carbon‐fiber‐reinforced poly(ether ether ketone) (PEEK) was used as a model system. The morphology and laminate quality were investigated on unidirectional laminates processed at cooling rates from 0.3 to 120°C/s and annealing of 177°C and 300°C. The laminate quality was examined for degree of consolidation, compaction, and fiber‐matrix uniformity. Combined calorimetric and density measurements, as well as micrographic techniques, were used for examination of the laminates. The fracture toughness for the laminate was measured as a function of the position over the thickness of a 40‐ply thick unidirectional laminate. This study clearly demonstrates the importance of uniform pressure distribution over the laminate to achieve a void free and homogeneous laminate.