Effects of different thermal-oxidative environments on mechanical properties of T800 carbon fiber/epoxy resin composites

Abstract

Different thermal-oxidative environments (70, 130 ℃ and 190 ℃) have important effects on the properties of carbon fiber composites. The mass loss characteristics of T800 carbon fiber/epoxy resin composites under different thermal-oxidative environments were analyzed, and the surface morphology, infrared spectra, dynamic mechanical properties and interlaminar shear properties of T800 carbon fiber/epoxy resin composites before and after aging were compared. The results show that in the initial stage of thermal-oxidative aging, the mass loss rate is increased rapidly, and the higher the aging temperature, the faster the mass loss. The extent of damage sample surface morphology is gradually increased with the increasing of thermal-oxidative temperature, after aging at 190 ℃, the resin on the fiber surface falls off seriously, the cracks and gaps appear between the fibers, and there is no resin filling, at this aging temperature, the sample has an irreversible chemical change. The glass transition temperature of the sample is increased with the increase of aging temperature, but the internal friction is decreased at first, then increased and then decreased. After thermal-oxidative aging at 70, 130 ℃ and 190 ℃, the shear strength of the samples is increased by 6.0%, 13.7% and 2.1%, respectively. The relevant test results and phenomena can provide data reference for the follow-up study of the new domestic T800 carbon fiber/epoxy composites.

Keywords

• different thermal-oxidative environment
• t800 carbon fiber/epoxy resin composite
• surface morphology
• infrared spectrum
• mechanical property