Jaber, A.A.; Abbas, S.A.; Farah, A.A.; Kopeć, K.K.; Alsalik, Y.M.; Tayeb, M.A.; Verghese, N. Effect of Fiber Sizing Levels on the Mechanical Properties of Carbon Fiber-Reinforced Thermoset Composites. Polymers2023, 15, 4678.
Jaber, A.A.; Abbas, S.A.; Farah, A.A.; Kopeć, K.K.; Alsalik, Y.M.; Tayeb, M.A.; Verghese, N. Effect of Fiber Sizing Levels on the Mechanical Properties of Carbon Fiber-Reinforced Thermoset Composites. Polymers 2023, 15, 4678.
Jaber, A.A.; Abbas, S.A.; Farah, A.A.; Kopeć, K.K.; Alsalik, Y.M.; Tayeb, M.A.; Verghese, N. Effect of Fiber Sizing Levels on the Mechanical Properties of Carbon Fiber-Reinforced Thermoset Composites. Polymers2023, 15, 4678.
Jaber, A.A.; Abbas, S.A.; Farah, A.A.; Kopeć, K.K.; Alsalik, Y.M.; Tayeb, M.A.; Verghese, N. Effect of Fiber Sizing Levels on the Mechanical Properties of Carbon Fiber-Reinforced Thermoset Composites. Polymers 2023, 15, 4678.
Abstract
It is well known that fiber sizing is one of the most important component in the manufacturing of composites, and it does affect the mechanical properties including strength and stiffness. In this work, the influence of fiber sizing levels on the mechanical properties of carbon fibers (CF) is reported at room temperature by using single fiber tensile testing (Favimat+), single fiber pullout testing (SFPO), and interfacial elemental analysis using X-ray photoelectron spectroscopy (XPS). Standard modulus of CF (7±0.2 μm in diameter) were sized using two Michelman commercially available sizing formulations. The average solid content for each sizing formulation is 26.3 ± 0.2% and 34.1 ± 0.2%, respectively. HEXION RIMR 135 with curing agent RIMH 137 was used as a model thermoset epoxy matrix during the SFPO measurements. A predictive engineering fiber sizing methodology is also developed. Sizing amounts of 0.5, 1, and 2 wt. % on the surface of the fiber is achieved for both sizing formulations. For each fiber sizing level, 50 single fiber tensile testing experiments and 20 single fiber pull-out tests were conducted. The ultimate tensile strength (σult) of the carbon fibers and the interfacial shear strength (τ_app) of the single fiber composite were analyzed. it is also investigated the effect of the sizing levels on the interfacial shear stress and the O/C (Oxygen/Carbon) surface composition ratio. As a result, generalized fiber sizing and characterization methods were established. The developed methods can be used to characterize the strength and interfacial shear strength of any man-made fibers with different sizing formulations and solid contents, irrespective of the matrix i.e. thermoset or thermoplastic.
Keywords
Carbon fiber; thermoset; sizing; single fiber tensile testing; single fiber pullout testing; sizing levels; X-ray photoelectron spectroscopy (XPS)
Subject
Chemistry and Materials Science, Materials Science and Technology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.