泡沫铝变形与吸能特性研究

目的研究密度、孔洞分布以及加载应变率对泡沫铝材料变形行为和吸能特性的影响。方法对3种不同密度范围的泡沫铝材料进行不同应变率下的压缩实验研究。结果实验结果显示,在10 mm/min加载速率下,密度范围为0.27~0.33 g/cm3和0.47~0.53 g/cm3的泡沫铝材料平均屈服应力分别为1.3和7.2MPa,平均应变能密度分别为0.8和3.8 MJ/m3。此外,密度为0.453 g/m3但孔洞分布不均匀的泡沫铝应变能密度为3.26 MJ/m3,密度为0.449 g/m3但孔洞分布均匀的泡沫铝应变能密度为3.84 MJ/m3。结论随着密度的增加,泡沫材料的屈服应力以及对应于不同应变时的应力均增加,而孔洞分布均匀的泡沫材料的能量吸收能力明显优于孔洞分布不均匀的泡沫材料,此外,加载速度对泡沫材料的应力应变行为有一定的影响,但对其能量吸收能力并无影响。

Deformation and Energy Absorption of Aluminum Foam

The work aims to study the effect of density, hole distribution and load strain rate on the deformation and energy absorption of the aluminum foam. The compression experiment study was conducted on the aluminum foam with three different ranges of density under various strain rates. The experiment results showed that, under the loading rate of 10 mm/min, the average yield stresses of the foam with the density ranges of 0.27~0.33 g/cm3 and 0.47~0.53 g/cm3 were 1.3 and 7.2 MPa, respectively. The average strain energy densities of these two foams were 0.8 MJ/m3 and 3.8 MJ/m3, respectively. Furthermore, the strain energy density of the foam (0.453 g/m3) with a nonuniform distribution of the hole was 3.26 MJ/m3, while the strain energy density of the foam (0.449 g/m3) with a uniform distribution of the hole was 3.84 MJ/m3. With the increasing density, the yield stress and the stress of the foam corresponding to various strains are increased. The energy absorption ability of the foam with the uniformly distributed holes is much better than the foam with the nouniformly distributed holes. Moreover, the loading rate has certain effect on the stress-strain behavior of the foam, but it has no effect on the energy absorption ability of the foam.