泡沫铝夹芯板抗冲击性能分析

试验设计了3块钢板夹泡沫铝夹芯板，厚度分别为50 mm、70 mm和100 mm。对每种厚度夹芯板进行七组不同落锤高度的冲击试验，测得了上、下面板变形值，记录了夹芯板的破坏情况。应用数值模拟软件ANSYS/LS-DYNA进一步还原夹芯板冲击过程，导出了面板与芯材的吸能占比。基于假设的夹芯板理论模型，给出了平均冲击荷载、局部变形和整体变形最大值的估算公式。结果表明:当夹芯板尺寸和材料强度一定时，局部变形值与落锤高度的平方根成正比，整体变形最大值、平均冲击力均与落锤高度的平方根成线性关系。夹芯板的抗冲击性能主要依靠增大泡沫铝芯层的变形进行耗能，芯层越厚，泡沫铝吸能占比越大，局部变形越小，夹芯板受到的冲击力越大。

ANALYSIS ON IMPACT RESISTANCE OF ALUMINUM FOAM SANDWICH PANELS

An experiment including three aluminum foam sandwich panels with the thickness of 100 mm, 70 mm and 50 mm was designed. For each panel, drop hammer impacts of seven different heights of were carried out to acquire the deformation of the upper and lower panel, and to record the collapse process of the sandwich panel. The impact process was simulated by ANSYS/LS-DYNA, and the energy absorption ratio of the face-sheets and the core to the whole sandwich panel was derived. Based on the hypothesis of a theoretical model, the estimating formulae of the average impact load, local deformation and maximum total displacement were given. The results show that the local deformation is proportional to the square root of dropping height, while both the maximum global deformation and the average impact load have a linear relationship with the square root of the dropping height for the sandwich panel with fixed sizes and materials. The anti-impact property of the sandwich panel is mainly dependent on the increase of the deformation of the aluminum foam. The thicker the core layer is, the larger the proportion of foam aluminum absorption energy is, the smaller the local deformation is, and the greater the impact force of the sandwich panel is.