Title: INTER-PLY CHARACTERIZATION OF PREPREG FABRICS FOR FORMABILITY

Authors: Eileen E. Miller, Zachary T. Verran, Richard A. Prause, Francisco P. Salinas-Fiesco

DOI: 10.33599/nasampe/s.23.0298

Abstract: State of the art commercial aerospace stringer-stiffened skins use 3 styles of toughened carbon/epoxy prepreg material forms: unidirectional tape, plain weave, and a biased plain weave. Despite manufacturing improvements, wrinkles remain a challenge for complex, highly contoured structure. With future production systems increasing rates, there is a need to enable 100% automation and first pass quality. Several prepreg fabric weave styles are available in industry, each with varied degrees of attributes affecting the conformability of the prepreg to complex contour. Previous studies of individual ply mechanisms, including intra-ply stiffness, bending stiffness, and bulk factor, have shown that Hexcel PrimeTex® 4H satin weave offers improved formability and reduced bulk over the state of the art material fabric architectures. The current study expands that work by characterizing inter-ply behavior to understand if the intra-ply compliance advantages hold for ply stacks.

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Conference: SAMPE 2023

Publication Date: 2023/04/17

SKU: TP23-0000000298

Pages: 15

Price: $30.00