Multiaxial mechanical behavior of aramid fibers and identification of skin/core structure from single fiber transverse compression testing
Year: 2015
Type: article
Abstract: The transverse and longitudinal mechanical properties of aramid fibers like Kevlar™ 29 (K29) fibers are strongly linked to their highly oriented structure. Mechanical characterization at the single fiber scale is challenging especially when the diameter is as small as 15 µm. Longitudinal tensile tests on single K29 fibers and single fiber transverse compression test (SFTCT) have been developed. Our approach consists of coupling morphological observations and mechanical experiments with SFTCT analysis by comparing analytical solutions and finite element modeling. New insights on the analysis of the transverse direction response are highlighted. Systematic loading/unloading compression tests enable to experimentally determine a transverse elastic limit. Taking account of the strong anisotropy of the fiber, the transverse mechanical response sheds light on a skin/core architecture. More importantly, results suggest that the skin of the fiber, typically representing a shell of one micrometer in thickness, has a transverse apparent modulus of 0.2 GPa. That is around more than fifteen times lower than the transverse modulus of 3.0 GPa in the core. By comparison, the measured longitudinal modulus is about 84 GPa. The stress distribution in the fiber is explored and the critical areas for damage initiation are discussed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 374–384
DOI: 10.1002/polb.23763
Institutions: Centre National de la Recherche Scientifique, ParisTech, Université Paris Sciences et Lettres, Michelin (France), Centre des Matériaux, Sciences et Ingénierie de la Matière Molle, École Nationale Supérieure des Mines de Paris, ESPCI Paris, Sorbonne Université, Université Pierre-et-Marie-Curie
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2168819841