W. Z. Li

Carbon nanotubes were grown directly on carbon fibers using chemical vapor deposition. When embedded in a polymer matrix, the change in length scale of carbon nanotubes relative to carbon fibers results in a multiscale composite, where individual carbon fibers are surrounded by a sheath of nanocomposite reinforcement. Single-fiber composites were fabricated to examine the influence of local nanotube reinforcement on load transfer at the fiber/matrix interface. Results of the single-fiber composite tests indicate that the nanocomposite reinforcement improves interfacial load transfer. Selective reinforcement by nanotubes at the fiber/matrix interface likely results in local stiffening of the polymer matrix near the fiber/matrix interface, thus, improving load transfer.

The Zylon fiber-reinforced polymer (ZFRP) reinforcements of pulsed magnets often manifest transverse and shearing failure modes under ultrahigh magnetic fields, resulting in unintended disruptions of the magnet system. Nevertheless, the transverse tensile, compression, and in-plane shear behaviors of ZFRP remain insufficiently understood, impeding efforts to elucidate the underlying failure mechanisms and enhance magnet performance. To address this knowledge gap, this paper undertook a comprehensive mechanical tests of ZFRP. Specimen were fabricated using the autoclave-forming technique, followed by transverse tensile, compression and in-plane shear tests conducted at 213 K, 243 K, and 296 K. The elastic modulus and stress-strain response were both characterized, and the influence of the fiber-filling factor were also discussed.