Storage Life Prediction of Carbon Fiber Composites Based on Electrical Conductivity

Carbon fiber composites are widely used in machine manufacturing because of their excellent characteristics. However, their service life is affected by the surrounding environment. Therefore, it is urgent to establish a life prediction model that provides a certain theoretical basis for the basic application of actual carbon fiber composite materials. Suitable models for the storage life prediction of carbon fiber composites were established under certain storage conditions by investigating the aging behavior of the composites composed of T700/epoxy resin. The variation of conductivity of carbon fiber composites under different thermal and oxygen conditions were studied, and the reasons were explored from the perspective of the aging mechanism. An empirical model for life prediction of the thermal oxidative aging law was established using kinetic formula and linear kinetic curve method, and the aging life at 25 celcius was predicted. At the same time, through exploring the electrical properties of carbon fiber composites, it is found that temperature and humidity jointly affect the aging life of the materials. Therefore, the wet and thermal aging life model derived by combining the Arrhenius model and Eyring model was adopted to predict the aging life under the condition of 25 celcius and 60% relative humidity (60% RH). Residual strength model and environmental equivalent were used to predict the damp and heat aging life under different testing conditions. The life prediction is helpful to establish a sound material evaluation system and a systematic safety protection system in practical applications.