Investigation of a 3D Printing Method for Continuous Carbon Fiber-Reinforced Thermosetting Epoxy Composite

Abstract

A novel 3D printing method for continuous carbon fiber-reinforced thermosetting epoxy resin composites (CCFRTC) was proposed, including CCFRTC prepreg filament manufacturing, secondary impregnation, printing and curing stages. Through the addition of an impregnation stage before printing, this method ensures a close interface bond and uniform distribution of fibers and resin. After testing, the average tensile strength and tensile modulus of the uncured pre-impregnated continuous filaments were found to be 968 MPa and 58.6 GPa, respectively. Mechanical testing of the specimens revealed that the maximum tensile strength and flexural strength of the CCFRTC specimens reached 825 MPa and 557 MPa, with tensile and flexural modulus measuring 157 GPa and 185 GPa. Furthermore, scanning electron microscopy (SEM) examination of the cross-sections indicated a highly uniform impregnation of both the filaments and printed specimens. In conclusion, the method proposed in this study enables the preparation and printing of continuous fiber-reinforced thermosetting resin composite materials, addressing the issues of inadequate impregnation and poor interfacial bonding performance in continuous carbon fiber-reinforced thermosetting resin composite materials. These findings may broaden the potential applications of 3D printing CCFRTC in the aerospace, defense, and automotive industries.

Graphical Abstract