闭孔泡沫铝的动态压缩性能试验研究

发布时间：2018-08-27 15:38

【摘要】：为了研究闭孔泡沫铝动态压缩性能的应变率效应,采用改进的INSTRON高速动力加载系统,对不同应变率下闭孔泡沫铝试件进行动态压缩试验研究。首先利用正向试验和反向试验技术对不同厚度的闭孔泡沫铝试件在同一加载速率下的动态压缩性能进行了研究,得到了在一定速率下消除泡沫铝动态压缩试验中惯性效应的合理试件厚度。进一步开展了闭孔泡沫铝试件在不同加载速率下的高速压缩试验,研究了其动态压缩性能随应变率的变化规律。结果表明在高速压缩下,闭孔泡沫铝的应力-应变曲线与准静态条件相同,具有明显的弹性段、平台段及压实段的3阶段特征。闭孔泡沫铝的平台应力具有明显的应变率效应,而致密应变在不同的应变率下表现出了不同的变化趋势,初步解释为泡沫铝孔壁塑性变形机制的改变以及波动效应的相互影响。闭孔泡沫铝的吸能能力随应变率的增加而明显提升。
[Abstract]:In order to study the strain rate effect of closed cell aluminum foam under dynamic compression, an improved INSTRON high speed dynamic loading system was used to study the dynamic compression test of closed cell aluminum foam specimens at different strain rates. In this paper, the dynamic compression properties of aluminum foam specimens with different thickness at the same loading rate are studied by using forward test and reverse test. The reasonable specimen thickness is obtained to eliminate the inertial effect in the dynamic compression test of aluminum foam at a certain rate. Furthermore, the high speed compression tests of closed cell aluminum foam specimens at different loading rates were carried out, and the variation of dynamic compressibility energy with strain rate was studied. The results show that the stress-strain curve of closed cell aluminum foam under high speed compression is the same as that of quasi-static condition, and it has obvious three stage characteristics of elastic section, platform section and compaction section. The platform stress of closed cell aluminum foam has obvious strain rate effect, while the dense strain shows different trends at different strain rates, which is primarily explained by the change of plastic deformation mechanism of aluminum foam wall and the interaction of wave effect. The energy absorption capacity of closed cell aluminum foam increases with the increase of strain rate.
【作者单位】：天津大学建筑工程学院;天津大学滨海土木工程结构与安全教育部重点实验室;
【基金】：国家自然科学基金项目(51238007;51378347)
【分类号】：TG146.21;TB383.4

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