Mechanical performance of 3D-printing plastic honeycomb sandwich structure

In this study, Bi-Grid, Tri-Grid, Quadri-Grid and Kagome-Grid honeycombs were designed and fabricated using 3D printing technology Sandwich composites were prepared by gluing the cores and composite face sheets together. Mechanical performance of the sandwich structures were characterized using finite element analysis and three-point bending test. Results indicate that when suffering from bending loads, the stress concentrations are located at the loading zone on upper face sheets (distributed in both sides of the indenter) and supporting zone on bottom face sheets, and the stress concentration zones of the honeycomb cores are located in the area that between indenter and supports. The failure mechanism of the Bi-Grid sandwich structure is interfacial de-bonding between composite face sheet and Bi-Grid core, and the failure modes of the Tri-Grid, Quadri-Grid and Kagome-Grid are core shear. The mechanical performance of Quadri-Grid sandwich structure is better than that of the other three structures.