Enhancing structural performance of recycled fiber-reinforced thermoplastic composite part through incorporating composite laminate precuts

The mechanical recycling process of fiber-reinforced composite parts involves shredding long continuous fibers into shorter discontinuous fibers. Since the performance of the shredded short fibers is not as high as that of the original long fibers, the application of recycled composites is limited. The objective of this study is to enhance the structural performance of recycled composite parts by integrating of a set of continuous fiber composite precuts during the molding process. The 2-dimentional precuts were positioned in the structurally critical regions of the recycled composite part, and the remaining area was then filled with shredded composite material. An aircraft overhead bin door pin bracket was used as the part geometry. The mechanically recycled material and the precuts were made from 60% by weight carbon fiber reinforced polyetherketoneketone (PEKK) composite. Three different combinations of precuts were designed to create the pin bracket, and their performance was assessed by mechanical testing of the pin bracket. Additionally, digital image correlation (DIC) technology was used to analyze local strain changes and investigate the failure mechanisms of the parts throughout the testing process. The test results demonstrated that the inclusion of properly designed precuts significantly improved the performance of the recycled composite part.