Title: EFFECT OF CURE ON MECHANICAL PROPERTIES OF MTM 45-1 MATRIX COMPOSITE
Authors: Scott Nesbitt, Hannes Koerber, Anoush Poursartip, Casey J. Keulen
Abstract: Current specifications for cure cycles define a process window within which the part is 'acceptably' cured. It has been well-known for a very long time that the degree of cure affects mechanical properties, but there is limited data currently available in the open literature to demonstrate the effect. As thermal simulation and management becomes better and more sophisticated, there is opportunity to better understand and control thermal histories - either for tighter material control, or to understand process deviations and excursions. This paper discusses thermal management of the curing process and identifies potential situations where a composite may be under-cured or thermally degraded (exposed to excessive temperature during cure). Results of 81 mechanical tests are presented, including tensile, compression, in-plane shear (V-notch rail shear), and short-beam strength on specimens that have been significantly under cured, moderately under-cured, cured according to the manufacturer’s recommended cure cycle, and thermally degraded to identify the effect this has on mechanical properties. This data is compared to NCAMP data as a benchmark. Analytical testing is used to verify properties of the variably cured resin including DOC and Tg. Cure simulation is used to plan out the cure process and provide insight into the results.
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Conference: SAMPE 2023
Publication Date: 2023/04/17
Price: $30.00Get This Paper