多孔材料填充薄壁结构吸能的相互作用效应

研究多孔材料填充薄壁结构的相互作用效应产生的机理，并建立了表征模型. 以泡沫 铝填充帽形结构为例，发现压溃的填充物分为致密区、过致密区和未变形区3个区域. 基于 理想可压缩假设建立了填充多孔材料分析模型，获得各区域体积变化和等效应变等关系；结 合薄壁结构超叠缩单元模型，对填充结构各组分的能量吸收进行了拆分. 研究表明，薄壁结 构的吸能略有增加，多孔材料的吸能增加40{\%}左右. 过致密区的形成是相互作用效应的 主要原因.

Interaction effect in energy absorption of porous material filled thin-walled structure

The mechanism of "interaction effect" raised in porous material filled thin-walled structure is studied, and quantitative partition in energy absorption is reached with the proposed model in this paper. Taking aluminum foam filled hat section as example, we found three characteristic regions in the crushed foam filler, i.e., densified region, extremely densified region and undeformed region. An analytical model according to the experimental observation was built to find the volume reduction and volumetric strain in each region of the crushed porous material filler, based on the perfectly compressible assumption. Combining with the superfolding element model for thin-walled hat structures, the contribution of each component of the filled structure, i.e., hat section, porous filler; densified region and extremely densified region to the overall energy absorption was quantitatively partitioned. The study shows that little increase in energy absorption is found in the thin-walled structure, while the augmentation in porous material filler is about 40%. The extremely densified region accounts for mainly to the interaction effect.