Interfacial Engineering of CFRP Composites and Temperature Effects: A Review

Carbon fiber-reinforced polymer (CFRP) composites are widely used in many industries due to their outstanding multifunctional properties. The durability and performance of these materials depend on their mechanical properties and fiber/matrix interface. A good interface ensures not only efficient load transfer but also long-term safety. Studies demonstrate that composites are affected by moisture, ultraviolet irradiation, and cyclic temperature variations. This review focuses on the performance of CFRP at high and cryogenic temperatures. There is a critical need to characterize and predict composite interfacial performance under different temperature fluxes. This paper presents an overview of the fiber-matrix interface at different temperatures and strain rates. First, interfacial mechanisms, mechanical tests, physical and chemical characterization techniques, and numerical simulations are introduced. Then, the effect of high temperatures, low temperatures, and strain rates on the composite’s interface are discussed. Interfacial adhesion is quantified utilizing different experimental techniques, including Iosipescu, short beam shear, fiber pullout/pushout, and fragmentation tests. While these report different interfacial strength values, factors that affect this variability are studied. High temperatures greatly decrease the interface strength of polymer matrix composites (PMCs) at temperatures above the resin’s glass transition temperature ( T g ). Cryogenic temperatures create micro-cracks between the fiber and polymer matrix. While mechanical tests, morphology observations, and chemical analysis help explain interfacial debonding after testing, these cannot explain the debonding process during testing. Simulation techniques add to the fundamentals of mechanics and predict the interfacial debonding process, and the methods to predict interfacial failure in extreme environments are discussed.