Crushing resistance tailoring of honeycomb material via vertex-derivative strategy

Abstract

To support the high protection requirements of advanced equipment, honeycomb materials are encountering more demanding challenges on their flexible design and mechanical properties. Therefore, a novel hierarchical topology, namely vertex-derived strategy, is proposed to pursue a superior crushing resistance for honeycomb materials. Based on this strategy, the honeycombs with vertex-derivative characteristic are developed to investigate their energy absorption mechanism and mechanical property under the axial impact. An efficient energy-absorbing progressive folding mechanism is experimentally triggered due to the refinement of the material distribution by sub-cells. Further, a numerical study is conducted to uncover the effect of the derivative index and the thickness-length ratio of the sub-cell on the crushing resistance of honeycomb. The result shows that the derivative index and the thickness-length ratio can improve the energy dissipation capacity and crushing force efficiency of vertex-derivative honeycomb (VDH). A numerical comparison on the material utilization indicates that the vertex-derivative hexagonal topology is a superior geometry for energy dissipation than the vertex-derivative quadrilateral topology under the same geometric parameters. In addition, a theoretical solution derived by the simplified super folding element (SSFE) theory reveals the quantitative relationship of the derivative index and the sub-cell geometry parameters on the energy absorption. The present study looks forward to proposing effective suggestions to enhance the crushing resistance of the hierarchical honeycomb by the vertex-derived strategy.