Material extrusion 3D printing of PEEK/PTFE composites with enhanced tribological behaviors and high precision

The global challenge of friction-induced energy dissipation in mechanical systems drives the demand for high-performance polymers with superior tribological properties. Poly(ether ether ketone) (PEEK) is a promising high-performance polymer for lightweight robots, yet its use in moving components is hindered by poor lubricity, high wear rate, and limited processability. Here, we adopted a facile tactic to fabricate a PEEK-based composite by filling polytetrafluoroethylene (PTFE) micropowders through material extrusion 3D printing. This composite enables the rapid prototyping of complex architectures with high printing resolution at the micrometer scale, providing excellent mechanical toughness and superior tribological properties. Specifically, the printed composite with 7.5 wt% PTFE showed the high-quality microstructure (PTFE size below 5 µm), excellent impact strength up to 81.72 kJ/m 2 , and high crystallinity of PEEK phase up to 29.24%. The resultant composite achieved the synergistic enhancement of lubricating and anti-wear properties at various loads (30–100 N), which was attributed to the lubricative transferred film led by PTFE. The average friction coefficient was remained at approximately 0.1 under various loads, with a minimum wear rate of 2.72 × 10 −5 mm 3 /(N∙m) at 50 N. To reveal the potentials, the porous oil-containing material, bearing and car differential are demonstrated by 3D printing. This printed PEEK/PTFE composite paves the way for enhancing the tribological performances and manufacturing flexibility in polymers, advancing the development of PEEK materials in high-precision transmission devices.