撞击作用下泡沫铝填充结构吸能特征

泡沫铝是由金属铝制成,由于铝具有较低的强度,导致泡沫铝本身的承载能力和吸能特性受到局限.典型的抗振吸能结构是泡沫铝填充结构或夹芯结构.采用实验和数值模拟方法分析了泡沫铝填充结构在冲击作用下的变形特征与吸能特性.研究表明,填充结构中钢制圆柱壳在整个冲击吸能过程中占主要地位,它与泡沫的相互作用使得变形过程中的能量吸收和初始失稳载荷随冲击速度的提高而增加;当钢制圆柱壳的壁厚增加时,峰值塌陷载荷和总的吸能也提高.在100 kg范围内,冲击质量对初始峰值塌陷载荷的影响不大.由于钢壳是主要的承载和吸能部件,要想提高泡沫铝填充结构的吸能特性,需要合理地设计泡沫密度与钢壳厚度,充分利用它们之间的相互作用关系.

Energy absorption of foamed aluminum-filled structures subjected to explosive and impact loadings

The carrying capacity and energy absorption characteristics of the foamed aluminum, made from metal aluminum, are limited due to the lower strength of aluminum. The typical antivibration energy absorbing structures are designed as foamed aluminum filled or sandwich structures. The deformation and absorption characteristics of the foamed aluminum filled structures subjected to impact loadings were analyzed using experimental and numerical methods. The results show that the steel shell of sandwich structures dominates during energy absorption. The energy absorption capacity and initial instability loading increase with the increase impact velocity and shell thickness, clue to the interaction between the steel shell and foam. The impact mass has little influences on peak instability loading within the range of 100 kg. Since the steel shell is the dominating part of load capacity and energy absorption, the reasonable design, taking into account of foam density and shell thickness and taking full advantage of interaction between steel shell and aluminum foam, should be adopted to increase the energy absorption characteristic of filled structures.