Mechanism and performance of thermal radiation recycling for in-space 3D printed continuous carbon fibre-reinforced PEEK composites

The benefits of space recycling lie in reducing launch mass and achieving self-sufficiency. For 3D printed continuous fibre-reinforced composites (CFRCs), a reverse melt recycling technology was proposed, involving heating resin opposite to the 3D printing path and continuously peeling-off the fibres from the melt. An infrared radiation heating recycling device suitable for a vacuum environment was designed and the temperature distributions were optimised, achieving recycling of continuous carbon fibre-reinforced polyether ether ketone (CF/PEEK) thin-walled rotational structures. The recycled filaments with diameters of 0.7 and 0.8 mm could achieve good surface quality and low pore defects. The porosity decreased from 11.2% of original samples to 5.7% of remanufactured samples, leading to improvements in mechanical properties with flexural strength and modulus increased by 4.8% and 50.8% respectively. Overall, the recycling technology emphasised a non-degradation recycling solution for 3D-printed CFRCs in space to form a full lifecycle application model for space composites.