The effects of processing parameters on the wedge peel strength of CF/PEEK laminates manufactured using a laser tape placement process

Manufacturing thermoplastic composites (TPCs) with excellent mechanical properties require advanced methods with reduced costs and better overall efficiencies. In this study, fiber-reinforced thermoplastic polymer composite laminates were manufactured using an automated fiber placement (AFP) manufacturing technology. The effects of processing temperature (from 320 to 500 ℃), lay-up speed (from 20 to 260 mm/s), consolidation force (from 100 to 600 N), and prepreg tape tension (from 0 to 9 N) on the quality of the resulting laminates manufactured using the laser AFP system were investigated. The interlayer bond strength was characterized using wedge peel tests on samples prepared with different process parameters. The studies were complemented by measurements of the thermal properties of the composites using differential scanning calorimetry. The optimized process parameter windows were determined to be 360 to 400 ℃ for the irradiation temperature, 140 to 160 mm/s for the lay-up speed, 100 N for the consolidation force, and 3 to 5 N for the prepreg tape tension, respectively. The microscopic analysis of the sample cross-sections and peel-damaged surfaces revealed that the different distributions of the resin matrix resulting from the different processing parameters affected the interlayer strength. These results may provide an important reference for manufacturing TPC used in aerospace, defense, and automotive applications.