Effects of Low-pressure Annealing on the Performance of 3D Printed CF/PEEK Composites
Xiao Yu, Wenzhe Song, Jing‐Hua Zheng, Yiwei Chen, Linlin Luo, Congze Fan, Zhongde Shan
Abstract
The interlayer bonding properties are normally unsatisfying for 3D printed composites owing to the layer-by-layer formation process. In this study, low-pressure annealing was performed on 3D printed carbon fiber reinforced polyether ether ketone (CF/PEEK) to improve the interlayer bonding strength. The effects of annealing parameters on the mechanical properties and microstructure were studied. The results showed that the interlaminar shear strength (ILSS) of CF/PEEK improved by up to 55.4% after annealing. SEM and μ-CT were also applied to reveal the reinforcing mechanism. This improvement could mainly be attributed to the increased crystallinity of the CF/PEEK after annealing. Additionally, annealing reduced the porosity of the printed CF/PEEK and improved the fiber–resin interface. This resulted in a reduction in the stress concentration areas during loading, thereby enhancing the interlayer bonding strength of CF/PEEK.