Abstract: There are many disadvantages for existing forming methods of polymer matrix composites which involve the low resolution, limited printed materials, and poor capability of making complex structures, tedious processes, etc. In particular, it is always a challenge issue to implement multi-scale fabrication for macro/micro structures with high effectiveness. A high-resolution 3D printing process of polymer matrix composites based on electric-field-driven fusion jet is proposed. The fundamental principle and process flow of the proposed method are described. Furthermore, the effects and rules of main process parameters (mass fraction of carbon filler, applied voltage, screw speed, printing speed, heating temperature, etc.) on the resolution (accuracy) and quality of printed parts are revealed by a series of experiments. Finally, using the experimental setup independently developed by the research group, combining with the optimized process parameters and two printing modes proposed, some typical cases are demonstrated which include the micro 3D grids of multi-layer graphene (MLG)/polylactic acid (PLA) and multi-walled carbon nanotubes (MWCNT)/PLA composites, the large-aspect-ratio thin-walled ring of MLG/PLA composite, and flexible conductive structures of MWCNT/PLA composite, as well as some PMC 3D functional parts. The results show that the new 3D printing process can implement the high resolution printing for various PMS (using the nozzle with an inner diameter of 300 μm, the feature size of 40 μm for PMC has been achieved), and the multi-scale manufacturing of macro/micro-structures made of MWCNT, MLG, short carbon fiber reinforcement material and PLA matrix material can be realized.

Key words: electric-field-driven fusion jetting, polymer matrix composites, high-resolution 3D printing, multi-scale fabrication