Title: Effect of Fast Cure Cycles on Mode I And Mode II Interlaminar Fracture Toughness for Interlayer Toughened Prepreg Composites

Authors: Cheng Chen, Anoush Poursartip and Göran Fernlund

DOI: 10.33599/nasampe/s.20.0016

Abstract: Faster cure cycles for thermoset prepreg composites are required to achieve higher production rates in the aerospace industry. This work studies the effect of fast cure cycles on the static Mode I (GIc) and Mode II (GIIc) interlaminar fracture toughness of an interlayer toughened composite material system, T800SC/3900-2B. Composite laminates were processed to the same degree of cure using a manufacturer's recommended cure cycle (MRCC), and three faster cure cycles with high heating rates (>2.8 °C/min) or high curing temperatures (>180 °C). The initiation and propagation GIc and GIIc were measured using Double Cantilever Beam (DCB) and End-notched Flexure (ENF) tests under static loading, respectively. Results show that curing conditions affect interlayer microstructures and the morphology of toughening particles. However, the initiation and propagation GIc and GIIc are not sensitive to the applied higher heating rates and curing temperatures. These results suggest that there may be an opportunity to greatly reduce the processing time for T800SC/3900-2B prepregs using faster cure cycles outside of the manufacturer's recommended processing window, yet retaining high interlaminar fracture toughness.

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Conference: SAMPE 2020 | Virtual Series

Publication Date: 2020/06/01

SKU: TP20-0000000016

Pages: 11

Price: FREE