Manufacturing of electroactive morphing carbon fiber/glass fiber/epoxy composite: Process and structural monitoring by FBG sensors

The aim of this paper is to design and develop a new class of electroactive carbon fiber/glass fiber/epoxy hybrid morphing composite with ability to change its shape in response to external stimuli. Morphing composites are of a great interest for aerodynamic structures to minimize the energy consumption and control the overall system performance. The hybrid asymmetric carbon fiber/glass fiber/epoxy morphing composite developed in this study provides a fine morphing controllability compared to classical morphing and bistable composites. In the conventional morphing structures, morphing ability is bestowed by only directionality of fibers from the same material. Herein, the morphing behavior stems from a mismatch in the coefficient of thermal expansion (CTE) between carbon and glass fibers. Fiber Bragg grating (FBG) sensors are used to monitor the manufacturing process of composites and to shed light on the physics behind the morphing behavior. Direct thermal loads are applied to the composite structure by using a temperature-controlled oven, hence manipulating its shape and in turn studying its morphing performance. Moreover, benefiting from electrical conductivity of carbon fiber reinforcement, the composite structures are provided with self-heating functionality based on Joule heating, which is used as an external stimulus for adjusting the shape of the composite structure.