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Abstract Manufacturing and investigating metallic‐glass‐fiber‐reinforced epoxies is an important new attempt to present their potential to contribute to the aviation industry. In order to explore the energy absorption in novel CoFeSiB metallic‐glass‐fiber/epoxy resin composites, CoFeSiB/epoxy resin composite cylinders with different fiber volume fractions were prepared by a hot‐pressing method. The amorphism of the metal fibers was analyzed using x‐ray diffraction. The quasi‐static compression tests were performed on different fiber oriented samples with a diameter of 3.6 mm and a height of 7.2 mm. The sample with the fiber orientation [0°/90°] has a higher energy absorption capacity, compared to the one with the fiber orientation [0°/0°]. The dynamic‐ compression tests were performed on the [0°/0°] samples with a diameter of 3 mm and height of 6 mm at different air pressures. The compression fracture surfaces were examined by scanning electron microscope. Then the energy absorption mechanism of the composites was investigated. This study is of great significance for the energy absorption in amorphous metal fiber/epoxy composites.
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Direct Fiber Model Validation: Orientation Evolution in Simple Shear Flow
Direct particle models are a promising tool for predicting microstructural properties of fiber reinforced composites. In order to validate our modeling approach for fiber orientation prediction, compression molded reinforced Polypropylene samples were subjected to a simple shear flow in a Sliding Plate Rheometer. Micro computed tomography was used to measure the orientation tensor for deformations up to 60 shear strain units. The fully characterized microstructure at zero shear strain was used to reproduce the initial conditions in the particle simulation. Fibers were placed in a periodic boundary cell and a flow field matching the experiment was applied. Samples created with the proposed compression molding technique showed repeatable and controlled initial orientation. The model showed good agreement with the steady state orientation; however, it showed a faster orientation evolution at the start of the shearing process.
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- Award ID(s):
- 1633967
- PAR ID:
- 10122984
- Date Published:
- Journal Name:
- Automotive Composites Conference and Exhibition
- Volume:
- 2019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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