Manufacturing method for high-amplitude corrugated thin-walled laminates

Abstract

Manufacturing of corrugated carbon-fiber reinforced composite laminates based on circular segments poses a challenge if high corrugation amplitudes create undercuts. This paper suggests to leave the formation of such high-amplitude corrugation shapes to thermal deformation of flat lay-ups which is effected by the difference between curing and service temperatures. It is shown by simulations that the method works best for carbon fibers of moderate stiffness and toughened epoxy-resin systems with high curing temperatures. Simple methods for predicting resulting shapes and stress distributions are explained and they verify non-linear structural simulations with FEM. A manufactured demonstrator validates the results. In addition to pointing out the new manufacturing method, some attention is paid to the potential application of corrugated laminates as flexible skins in morphing wings. It is pointed out how easily the morphing sections can be integrated into the manufacturing of wing skin and numerical stress analyses underline the strength feasibility of the manufacturing method. It comes as an additional benefit of the suggested manufacturing method that sliding overlaps can be integrated to create an aerodynamically smooth surface.