Title: CHARACTERIZATION TESTING OF UN-CURED PREPREG FABRICS FOR FORMING PROCESS

Authors: Malcolm Lane, Alireza Forghani, Michael Andersen, Paulo Silva, Simon Hind, Drazen Djokic, Meysam Rahmat, Ali Yousefpour, Goran Fernlund, Anoush Poursartip

DOI: 10.33599/nasampe/s.23.0053

Abstract: Composite forming is an automated process used to shape prepreg laminates into complex geometries to improve laminate fit-up and reduce layup labour. During a forming process, the laminate experiences large deformations, and the prepreg pre-gelation behaviour exhibits highly non-linear temperature and rate dependency. In-plane and transverse shear, ply bending, ply/tow slip and separation, and tool-part interaction are among the key deformation mechanisms seen. Due to the viscoelastic/plastic nature of thermosetting prepreg behaviour, processing conditions significantly influence the laminate’s non-linear behaviour and lead to a complex interaction of properties which makes process optimization difficult. Process optimization can be conducted using modelling but requires appropriate test methods to characterize the necessary material properties. In this paper we present both a new framework and novel test methods to characterize tack and ply bending for forming processes. A complete characterization data set for a standard carbon fibre-epoxy prepreg over the full forming temperature range is also presented and is believed to be the first dataset of its kind to be presented in open literature.

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Conference: SAMPE 2023

Publication Date: 2023/04/17

SKU: TP23-0000000053

Pages: 14

Price: $28.00