Effects of crystallinity control on mechanical properties of 3D-printed short-carbon-fiber-reinforced polyether ether ketone composites

A change in the crystallinity of short-carbon-fiber-reinforced polyether ether ketone (CF/PEEK) composites has a significant effect on the shrinkage deformation characteristics and mechanical properties of the components that are fabricated using 3D printing of CF/PEEK composites. In this study, we propose a novel process for controlling the crystallinity of 3D-printed CF/PEEK composites. First, components of a CF/PEEK composite with low crystallinity and warping deformation were 3D printed at a normal ambient temperature (20 °C). Second, the crystallinity and mechanical properties of the composite were quantitatively controlled via a recrystallization process. Finally, the mechanical properties of the CF/PEEK composite (10 wt%) were found to be similar to those of the materials fabricated via the injection molding process. This research work is of positive significance to promote the application of 3D printed PEEK composite materials in the field of aerospace and orthopedic implants.