A Zigzag-formed Truss Core and its Mechanical Performances

Abstract

Core with a high load-bearing capacity can be advantageous in improving the overall performance of a sandwich panel. For periodic cellular metal (PCM) cores in shapes such as an octet, pyramid, or Kagome truss, higher load capacity could be achieved by increasing the relative density of the core. Namely, short and thick truss struts composing the truss PCM results in high load capacity. However, the limit inherent in the topology or fabrication process of truss cores has been an obstacle to designing high-strength sandwich panels with single-layered truss PCM cores. In this work, a truss PCM core with new topology, essentially a variation of a conventional pyramidal truss, is introduced. With the new type of core structure, it is possible to increase the relative density of the core more easily, and consequently achieve higher load capacity of the core. Analytic solutions for normal and shear strength are derived, and compared with those for a pyramidal core. Experimental results are presented to show the structural performance of the new core structure under out-of-plane compression and in-plane shear loading. The design flexibility of sandwich panels with the new core is demonstrated, and potential applications are discussed.