Title: Impact of Prepreg Aging on the Mechanical and Fracture Behavior of Chopped Fiber Composites
Authors: Troy Nakagawa, Seunghyun Ko, Cory Slaughter, Talal Abdullah, Guy Houser, Marco Salviato
Abstract: The effects of prepreg out-time on the mechanical properties and fracture behavior of Discontinuous Fiber Composites (DFCs) are investigated. Carbon fiber prepreg is aged in an environmental chamber at a constant temperature and humidity. Tests are performed at 1x, 2x, and 3x the out-life of the prepreg, and compared with the non-aged DFC and quasi-isotropic properties. To quantify the aging, Differential Scanning Calorimetry (DSC) is performed to obtain the enthalpy of the prepreg. Microscopy is performed to investigate any changes in constituent content and mesostructure. Tension, compression, and shear tests are performed to see the effects of aging on these mechanical properties. Mode I intra-laminar fracture and size effect is also investigated by testing geometrically-scaled Single Edge Notch Tension (SENT) specimens. Finite element simulations are performed for SENT specimen to obtain the fracture energy and effective fracture process zone size of DFCs at various out-times. By investigating the effects of out-time, insight can be obtained on the viability of using DFCs to recycle prepreg waste. From the experiments, it was seen that the modulus did not change, and there was a slight increase in strength with age. These findings show that DFCs can be used to recycle prepreg without loss in performance.
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Conference: SAMPE 2022
Publication Date: 2022/05/23
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