Manufacturing and recycling of 3D printed continuous carbon fiber reinforced pla composites

Low-cost manufacturing and recycling technologies for high-performance continuous fiber reinforced composites are very important to industrial applications. A novel 3D printing based fabrication process of continuous fiber reinforced thermoplastic composites (CFRTPCs) was proposed. Continuous carbon fiber and PLA filament were utilized as reinforcing phase and matrix, respectively, and simultaneously fed into the fused deposition modeling (FDM) process realizing the integrated preparation and forming of CFRTPCs. When the fiber content of printed composite specimens reached 27%, flexual strength of 335MPa and modulus of 30 GPa were obtained. Recycling and remanufacturing strategy for 3D printed CFRTPCs was proposed to retrieve the carbon fiber and PLA matrix in the form of PLA impregnated carbon fiber filament, which could be reused as the raw material for CFRTPCs 3D printing process. Remanufactured CFRTPCs specimens also exhibited a 25% higher bending strength than that of original ones, which experimentally demonstrated the first non-downgrade recycling process for CFRTPCs. A material recovery rate of 100% for continuous carbon fiber and 73% for PLA matrix were achieved for a better environmental impact. Energy consumption of 67.7 and 66 MJ/Kg respectively for recycling and remanufacturing processes was detected and compared with conventional methods. The proposed cleaner production pattern offered a potential strategy for the low-cost industrial application of fully recyclable composites.