High-content continuous carbon fiber reinforced multifunctional prepreg filaments suitable for direct 3D-printing

3D printing of continuous carbon fiber reinforced composite is a hot research topic in the field of additive manufacturing in recent years, which provides a new idea for the design and manufacture of complex composite structures. At present, most of the studies have achieved the improvement of single mechanical property by changing the type of resin and fiber, increasing the fiber content, and improving the interface characteristic. Herein, nylon (PA6)-short carbon fiber/continuous carbon fiber (PA6-SCF/CCF) and nylon-carbonyl iron powder/continuous carbon fiber (PA6-CIP/CCF) multifunctional composite prepreg filaments were successfully prepared. The average diameter and tensile strength of the above two prepregs were 627.14 mu m, 1000.9 MPa, and 624.58 mu m, 723.9 MPa, respectively. The introduction of SCF and CIP effectively changed the electromagnetic characteristic of the composite prepreg filaments and improved the electromagnetic loss capacity. The effects of different fillers on mechanical and electromagnetic properties were analyzed through microstructure characterization of prepregs. This study has certain reference significance for expanding the application range of continuous carbon fiber reinforced composites suitable for 3D printing.