Characterization of Joule heating and deconsolidation behavior of continuous carbon fiber reinforced polyamide 6 composites under self‐resistance electric heating

Abstract As an effective heating method, self‐resistance electric (SRE) heating was applied for welding, hot stamping and curing process of composites. In this study, the characterization of Joule heating and deconsolidation behavior of continuous carbon fiber reinforced polyamide 6 (CFR‐PA6) laminate under SRE heating were investigated. A series of experiments were performed to build the relationship among geometry sizes, current density and temperature response. Then the relationship between the temperature rising rate and current density of CFR‐PA6 laminate with twill weave fabric was determined. The temperature evolution of specimen with a hole under SRE heating was also discussed. Furthermore, the deconsolidation behavior of CFR‐PA6 specimens under SRE heating as well as oven heating was characterized through macroscopic and mesoscopic properties. The interlaminar shear strength (ILSS) tests of specimens were also conducted. The results indicate that the temperature response of CFR‐PA6 laminate is mainly determined by the current density and their relationship can be described by a quadratic function. It is found that voids appear both inside the fiber bundles and resin‐rich areas owing to the thermal mismatch between the resin and carbon fibers after SRE heating, while no voids inside the fiber bundles were observed after oven heating. The deconsolidation behavior of laminate after SRE heating reduces the ILSS.