High accuracy 3D printing of composite materials using CNT yarns

Generally, the 3D printing of continuous carbon fiber involves using filaments with a large diameter. Consequently, this has made it particularly challenging to achieve precise printing and intricate detailing, particularly in curved sections. Therefore, in this study, we aim to evaluate the formability of CNT (Carbon nanotube) yarn as an alternative filament and compare it with the formability achieved with conventional filaments. Printing a single-layer circle using CNT yarn revealed that using CNT yarn enabled printing of circles with a setting radius of 0.9 mm, thus demonstrating the feasibility of submillimeter-scale printing, which was not possible with conventional filaments. Additionally, the maximum gap in the print width (= w) was reduced by approximately 73.7 % in circle printing and was reduced by approximately 69.5 % in bending printing, respectively. Thus, it can be asserted that the use of CNT yarns enables more precise printing of finer shapes.