Simmons, Reva N.; Lee, Harry; and Kim, Garam, "Investigation of Fiber Orientation and Mechanical Properties of Pyrolysis Recycled Carbon-Fiber Reinforced Thermoset Composite" (2023). Discovery Undergraduate Interdisciplinary Research Internship. Paper 52.
Date of this Version
recycled carbon fiber composites, pyrolysis, copper mesh, sustainability, microscopy, tensile testing
With increasing demand of carbon fiber reinforced fiber thermoset composites, establishing a sustainable cycle for these materials becomes crucial. Pyrolysis is a process of reclaiming carbon fiber from thermoset composites by thermally degrading the polymer at high temperatures allowing the fibers to be extracted. Carbon fiber reclaimed through current pyrolysis processes for thermoset composites typically loses its original shape and orientation, making it difficult to reorganize the fibers. This study investigated the feasibility of maintaining the fiber orientations for continuous fiber reinforced thermoset composite during pyrolysis by stitching the carbon fiber layup to a conformable copper mesh during the manufacturing process. By maintaining the carbon fiber lengths and orientation through pyrolysis, an identical part or similar part can be reproduced and significantly mitigate the fiber reorganizing process. This study used the two-step pyrolysis-oxidation process to reclaim the fibers and vacuum assisted resin transfer molding (VARTM) for sample manufacturing. The changes in fiber orientations were monitored over multiple VARTM-pyrolysis iterations using microscopy for plain weave samples, both with and without the copper mesh. The potential contamination within the plies during the pyrolysis process was thoroughly investigated, and approaches to remove it before the next VARTM process were developed. Additionally, the tensile strength and stiffness of both the control and copper mesh samples were measured at each iteration to assess the decrease in structural performance over multiple iterations.