Energy absorption behavior of closed-cell aluminium foam under drop mass impact tests

摘要

Quasi-static axial compression and drop mass impact tests were performed to study the energy absorption behaviour of the closed-cell aluminium foam. Digital image analysis was firstly used to characterize the surface's structure of individual cells and aggregates of cells. The cell structure characterizations performed using the best-fit ellipse equivalent diameter for the individual cells, which included measurement of the size distribution of cells, cell's aspect ratio and orientation. It shows that the statistical distribution of cells' size and cell's aspect ratio well follow Gauss distributions. The energy absorption behavior of the high porosities aluminium foam under static and drop weight impact compression were then conducted. High-speed imaging technique and temporal digital image correlation method were employed to evaluate the deformation and acceleration in the compression experiments. Using these approaches, the deformation and energy absorption mechanism of Al foam due to drop impact can be observed and better understood. The experimental results show that aluminium foams are quite close to a kind of isotropic structure and have high energy absorption capabilities.