Formability Characterization of Fiber Reinforced Polymer Composites Using a Novel Test Method

Fiber reinforced polymer composites are often used as a replacement for metal alloys because of the superior strength to weight ratio. However, major drawback these materials is lack formability caused by low strain failure ratio that does not allow material follow tooling contours into deep drawn shapes or tight radii. Composite have multiscale hierarchical structure where micro and meso scale effects (fiber tow scales) contribute macro structural response (laminate scale). In particular, during forming, different deformation occurs simultaneously at every scale. Currently, amount quantifiable comparable forming data both continuous discontinuous fiber composites, including multi-scale understanding response, limited testing system. This article proposes novel test method an apparatus called “the fixture” determining required load form uncured resin impregnated sample stretch profile. Test results from Hexcel (Stamford, CT) IM7-G carbon with Huntsman (The Woodlands, TX) RDM 2019-053 system, in temperature range 21°C–121°C, discussed demonstrate use proposed representative data. Results showed consistency repeatability, validating reliability method. The aided defining behavior real time visually (e.g. location) versus displacement curves. A metrics, relating maximum drawing depth no load, defined compare select formulations. Widespread adoption fixture will reduce reliance on “trial error” approach process.