Study on Hygrothermal Properties of Carbon Fiber Reinforced Composites Aged in Cyclic Environment

Abstract

In this study, we investigate the cyclic hygrothermal effects of moisture, high temperature and low temperature states on the durability of carbon fiber reinforced epoxy resin composites (CF/Epoxy). CF/Epoxy composites are prepared by curing in autoclave. The moisture diffusion behavior of CF/Epoxy composites is analyzed by moisture content as a function of time. In addition, the effects of cyclic conditions on the inter-laminar shear properties and microstructure of composites are investigated through inter-laminar shear strength (ILSS) tests and scanning electron microscope (SEM) analysis respectively. The test results show that composites have a good retention rate of ILSS. The SEM photographs, associated with the mentioned ILSS test results demonstrate that desorption cycle makes more remarkable degradation of ILSS compared to aging in water, and it is necessary to calculate the effect of low-temperature wet condition when we design accelerated aging cycle.