Laser-assisted AFP-TPC manufacturing of CF/PEEK high-performance thermoplastic composites with low warpage-deformation defects

This study aims to reveal the warpage-deformation defect generation mechanism in the automated fiber placement for thermoplastic composites (AFP-TPC). First, thermal characterization was carried out to obtain the processing window for the carbon fiber (CF)/polyetheretherketone (PEEK) composites. A temperature acquisition system with a sampling frequency of 100 Hz was used to measure the temperature of the consolidation process. Then, the effects of consolidation temperature (320–480 °C), consolidation force (100–500 N) and consolidation speed (50–250 mm/s) on warpage-deformation and residual stress of CF/PEEK composites were systematically investigated. The warpage degree calculation method was optimized by using a coordinate measuring machine and the residual stresses in CF/PEEK composites were measured by the hole-drilling method. It was observed that high consolidation temperature (480 °C), high consolidation force (500 N) and low consolidation speed (50 mm/s) led to an increase in warpage-deformation by 29.09 %, 15 % and 60 % respectively, corresponding to an increase in residual stress by 103.89 %, 97.44 % and 127.48 % respectively. This is due to the temperature gradient of the AFP-TPC process and the higher orientation of the PEEK polymer chains that occurs at these consolidation parameters, which leads to greater residual stresses and ultimately greater warpage-deformation defects. Ultimately, it was proposed that CF/PEEK composites with low warpage-deformation can be obtained by selecting lower consolidation temperature, consolidation force and higher consolidation speed. This study provides an effective method for the shape-integrated manufacturing of TPC components.