Title: Effect of Cure and Conditioning on the Fracture Properties of MTM45 Woven Carbon Epoxy Composite

Authors: Shayan Fahimi, Hannes Koerber, Scott Nesbit, Gabriel Valenzuela, Anoush Poursartip, Casey Keulen

DOI:

Abstract: Current specifications for cure cycles define a process window within which a composite part is 'acceptably' cured. It has always been well-known that the degree of cure affects mechanical properties, but there is limited data currently available to demonstrate the effect, especially under hot-wet conditions. This paper continues a study that was presented at SAMPE Seattle, 2023 and SAMPE Long Beach, 2024 by extending the investigation of the effect of various levels of degree of cure on dry and moisture conditioned samples at both ambient and elevated temperatures to explore fracture properties of MTM45 woven carbon epoxy composite. The results of over 70 mechanical tests under ambient-dry, ambient-wet, and hot-wet conditions including open hole tension (OHT, ASTM D5766), compression after impact (CAI, ASTM D7137), and double cantilever beam (DCB, ASTM D5528)/mode I interlaminar fracture toughness on specimens that have been moderately under-cured, and cured according to the manufacturer’s recommended cure cycle will be presented. This data is compared to NCAMP data as a benchmark. Analytical testing and cure simulations were used to plan out the cure process and verify the as-tested properties of the partially cured samples, including degree of cure and glass transition temperature.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 133

Pages: 12

Price: $24.00