泡沫铝合金动态力学性能实验研究

Experimental studies on the dynamic compressive properties of open-celled aluminum alloy foams

利用分离式霍布金森压杆(SHPB)实验技术和MTS材料实验机对两组不同孔径、不同密度的开孔泡沫铝合金进行了准静态和动态压缩实验研究。实验结果表明:泡沫铝合金的静态和动态变形过程均具有泡沫材料变形的“三个阶段”特征。开孔泡沫铝合金的变形是均匀变化过程,并不出现局部的变形带。与相对密度对力学性能的影响相比,孔径大小的影响可以忽略不计。在考察的应变率范围内,屈服应力对应变率并不很敏感。

The compressive deformation behavior of open-celled aluminum foams with different densities and morphologies was tested under quasi-static and dynamic loading conditions. High strain rate experiments were conducted using a split Hopkinson pressure bar technique at strain rates ranging from 500 s^-1 to 2 000 s^-2. The experimental results show that the compressive stress-strain curves of aluminum alloy foams are characterized by three stages appeared in general foam materials, namely elastic, collapse and densification ones. Compared with that of relative density, the effect of cell Size on the dynamic properties can be negligible. The yield stress is insensitive to strain rates, and the deformation is spatially uniform for the open-celled aluminum alloy foams in a wide range of strain rates.