Study on the aging properties of 3D woven composites under corrosive conditions

Different aging conditions have an important influence on the performance of carbon fiber composites. In this study, the properties of three-dimensional woven carbon fiber reinforced resin matrix composites were investigated and analyzed in three different aging environments (distilled water immersion, 30% H2SO4 solution immersion, and 10% NaOH solution immersion) at 60°C. Mass change, moisture absorption change, Fourier transform infrared spectra (FTIR), surface morphology before and after aging, glass transition temperature (Tg), compression properties, bending properties, and interlayer shear properties were analyzed. The results showed that the immersion in 10% NaOH solution made the specimens destroyed and the aging process was chemically changed. Distilled water immersion and 30% H2SO4 solution immersion moisture absorption rate to meet the FICK law, the aging process only physical changes. The surface of the composite specimens under the three aging conditions produced different degrees of cracks and different degrees of debonding at the interface between the fibers and the resin matrix. The Tg, flexural properties, interlaminar shear properties, and compressive properties of the aged specimens all showed different degrees of degradation.