3D orthogonal woven carbon fiber/PEEK composites with superior bending and flame-retardant properties

Thermoplastic composites have a wide range of applications in the industrial field. However, it is challenging to achieve three-dimensional (3D) multi-layer thermoplastic composites due to the poor impregnation of highly viscous thermoplastic resins. Herein, we propose a new preparation method to obtain 3D carbon fiber/PEEK (CF/ PEEK) composites with exceptional mechanical properties. CF/PEEK prepreg was used as the warp and weft yarns, and the Kevlar yarn was used as Z-yarns to weave 3D orthogonal preform through a self-made loom. 3D CF/PEEK composites were completed by hot-pressing process with varied resin contents from 37 wt% to 46 wt%. When the resin content was 43 wt%, the CF/PEEK composites exhibited the largest bending strength, with values of 248.5 MPa and 657.12 MPa along the warp and the weft directions, respectively. Additionally, the as-prepared 3D CF/PEEK composites could not be ignited and could retain around 90.67% of its original bending strength even after being subjected to the flame of an alcohol burner for 360 s. This work provides a novel method for fabricating 3D thermoplastic composites, a promising material in the field of high-performance composites.