Study of the effect of cured epoxy resin on the mechanical properties of large tow carbon fibers

The interfacial strength between carbon fibers and epoxy resin is one of the key factors affecting the strength of carbon fibers and has been the focus of researchers’ attention. It is necessary to consider it systematically because the stresses borne by the carbon fiber will be shared by the cured epoxy resin. In this paper, by constructing simulation models and tensile tests, we verified the changes of carbon fiber stresses in the presence and absence of epoxy resin, as well as under a variety of temperature conditions, and proved that epoxy resin curing does affect the changes of the tensile properties of large tow of carbon fibers. The results show that with the increase of load, the carbon fiber stress tends to increase nonlinearly, and the error value increases and the results of simulation calculation and experimental verification are basically in agreement. As the temperature decreases, the error value decreases slightly. These research results have important practical significance for the enterprise to reduce the cost and also have a reference for the simulation software on how to set the interface layer parameters.