Load-bearing and bending resistance characteristics of a new sandwich structure

Compared to traditional structures, the sandwich structures have higher strength, lighter weight, better impact resistance, as well as good thermal insulation. In this paper, a new cell structure is proposed by combining the elytra structure of the unicorn beetle with the concave hexagonal honeycomb structure. The cell parameters are optimized by the response surface methodology with the maximum energy absorption as the optimization objective. Based on this, the cell structure is periodically arranged as the core of the sandwich structure. The analyses of the simulation and experiment results show that the new sandwich structure exhibits higher initial peak value of supporting reaction force and energy absorption efficiency than that of the traditional concave hexagonal and regular hexagonal sandwich structures during the compression progress. The effects of different structure parameters on the bending resistance characteristics of the sandwich structure are analyzed. And the bending resistance characteristics of three kinds of the sandwich structures are analyzed by the simulation calculation and experiments. The results show that the new sandwich structure because of the arc and cylindrical design of the cell, effectively delays interface delamination and core collapse. Its ultimate bending load is significantly higher than that of the other two structures. The energy absorption is improved by 15% compared to the concave hexagonal sandwich structure and by 24% compared to the regular hexagonal sandwich structure.