Conical shells made by 4D printing of composites

Abstract

This paper presents a new, novel method for the manufacturing of composite cones. The method utilizes the principle of 4D printing of composites. The method does not require the use of a mold of conical shape, which is essential using conventional manufacturing methods such as filament winding or hand lay up. Instead, only a flat mold is required. In this technique, layers with different fiber orientations are laid on a flat mandrel. Upon curing and cooling to room temperature, the flat stack of composite layers will curl into the shape of a conical shell. When the edges of the shell are joined together by adhesive bonding, one has a structure that has the shape of a cone. Cones made using this new technique show axial buckling strengths that are comparable to those of cones made from similar materials with the same weight, using filament winding method. The buckling load and buckling mode shape are determined using finite element method. The results agree well with experimental results.