Tailored Universal Feedstock for Forming (TuFF) is a highly aligned discontinuous fiber (ADF) composite, developed to create composite laminates with metal-like formability. This material has shown fiber directional stretch while retaining fiber volume fractions up to 57%, demons
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Tailored Universal Feedstock for Forming (TuFF) is a highly aligned discontinuous fiber (ADF) composite, developed to create composite laminates with metal-like formability. This material has shown fiber directional stretch while retaining fiber volume fractions up to 57%, demonstrating the ability to create complex geometry components. Conventional stretchforming of ADF laminates results in an undesirable high number density of localized deformations, and non-uniformity in cure ply thickness and areal weight throughout the material. Emphasis is placed on achieving a consistently repeatable behavior of the material during stretch forming, aiming to minimize variability in material characteristics throughout the forming process steps. This objective responds to challenges faced in conventional stretchforming of ADF laminates, which tends to yield undesirable outcomes despite the material’s demonstrated capabilities. The study explores advancements in enhancing the formability of ADF thermoplastic materials, particularly through the application of confinement pressure and a comprehensive analysis of the materials’ microstructural behavior during stretchforming. Composite blanks consist of 8 ply thick cross-layup laminates, composed of 3 mm long IM7 carbon fibers with a semi-crystalline thermoplastic resin of Low-Melting Polyaryletherketone (LMPAEK). The report discusses crucial aspects associated with forming ADF composites, including their unique characteristics, processing considerations, and limitations. Additionally, it presents a case study of double-diaphragm forming process applied to the novel composite material TuFF. The upgradation presented by this work shows how relatively small amounts of confinement pressure allow for a significant improvement in part quality at aerospace-grade components.