Structural upcycling of thermoplastic composite recyclates through continuous fiber printed preforms

Abstract To enhance the structural characteristics of recycled composites, this paper demonstrates a process that incorporates additively manufactured continuous fiber preforms in a geometry that is compression molded with recyclates. The continuous fiber preform is designed to serve as the primary structural reinforcement whereas the recycled material serves as a secondary reinforcement in the composite part. Continuous fiber preforms were manufactured with 60% by volume of carbon fiber‐reinforced Poly Ether Ketone Ketone (PEKK) using Additive Fusion Technology (AFT) with account for reshaping during the molding process and ensure the continuous fiber is located where required. The performance of the upcycled composite pin bracket was evaluated by analyzing the onset of failure and the ultimate load under tensile loading of the bracket. The results demonstrated the potential of this upcycling method to enhance the structural characteristics of recycled composite materials and compensate for the loss of structural characteristics associated with fiber attrition. Highlights Continuous carbon fiber PEEK composite preforms were additively manufactured. Preforms (17% by weight) were integrated into the recycled composite part. The upcycled part showed significantly increased structural performance. Ultimate failure load improved by 57%–61% in the upcycled composite part. Onset failure load improved by 100% in the upcycled composite part.