Bending performance and failure behavior of 3D printed continuous fiber reinforced composite corrugated sandwich structures with shape memory capability

Abstract Here, a co-extrusion-based 3D printing technology was applied to integrally manufacture continuous fiber reinforced composite trapezoidal corrugated sandwich structures (CFRCTCSs) with shape memory capability. The theoretical models were developed to analyze the bending performance and failure behavior of the 3D printed CFRCTCSs with various geometric configurations and verified by three-point bending tests. Good agreement between the predictions and the experimental measurements was achieved. Considering four dominant failure modes including face yielding, face buckling, core shear failure and indentation collapse, the failure maps based on the analysis models were constructed to highlight the failure mechanism of CFRCTCSs and provide a practical guide for the design of lightweight sandwich structures. Shape recovery tests were performed to confirm the shape memory capability of the 3D printed CFRCTCSs. Finally, the comparison of the bending properties with several competing structures indicates that the 3D printed CFRCTCSs possess the potential to provide new opportunities for lightweight systems and multifunctional applications.