关键词: 工程仿生学, 纵向混合, 负泊松比结构, 耐撞性

Abstract: To improve the crash-resistance of the protective structure in the automobile structures, 24 energy absorption structures with bionic mixed negative Poisson’s ratio are designed by extracting the microstructure of the crayfish claw through biological experiments. Mass specific energy absorption (SEA), structural average crushing efficiency (CFE), and initial peak load (IPF) are taken as the main indexes to evaluate the crashworthiness of the structure. The validated finite element model is employed to simulate the design structure, and the key parameter a (depth of intracavity) affecting the crashworthiness of the structure is determined through the analysis of the final data. The optimal crashworthiness structure is selected by weighted combination comprehensive evaluation method according to actual working conditions. The results show when a=6.80 mm, the BCDA hybrid structure achieves the best crashworthiness, SEA=3.21 kJ/kg, IPF=8.58 kN, CFE=31.29% after optimization. Compared with the single cell structure, the optimized hybrid model decreases the IPF by 35.24% at most, increases the SEA by 35.72%, and decreases CFE by 47.20% at most. Our study may point a new direction for the design of energy absorption structures with negative Poisson’s ratio.