Ultrasonic Welding of Additively Manufactured PEEK and Carbon-Fiber-Reinforced PEEK with Integrated Energy Directors

The thermoplastic polymer polyether ether ketone (PEEK) offers thermal and mechanical properties comparable to thermosetting polymers, while also being thermally re-processable recyclable as well compatible with fused filament fabrication (FFF). In this study, the feasibility of joining additively manufactured PEEK in pure short carbon-fiber-reinforced form (CF-PEEK) is investigated. Coupon-level samples for both materials were fabricated using FFF tailored integrated welding surfaces two different energy director (ED) shapes joined through ultrasonic welding. Using an energy-driven process, systematically investigated parameters, such force, oscillation amplitude power, against resulting weld quality. strengths welded bonds characterized lap-shear tests benchmarked monotonic single 3D-printed samples, yielding ultimate forces 2.17kN 1.97kN tensile 3.24MPa 3.79MPa CF-PEEK, respectively. microscopically imaged characterize failure behaviors joints parameters. Samples optimized parameters exhibited failures outside region, indicating a higher weld-strength compared that bulk. This study lays foundation glue-free method join high-performance thermoplastics manufacture large load-bearing, non-load-bearing, structures, minimizing time cost limitations process.