摘要
以椭圆拟合长方体闭孔多边形泡沫铝表面孔截面,运用统计学的方法研究了泡沫铝试件表面孔的大小、形状和方位等分布特征.统计结果表明:上述孔的各项几何特征参数除方位外服从高斯分布.应用图像处理技术,获取了单轴压缩变形前后泡沫铝试件的表面图像.利用序列数字图像相关方法对泡沫纯铝变形前后的图像进行相关计算,获得了静态单向压缩条件下闭孔泡沫铝材料表面全场变形及局部孔结构的变形,同时根据试验结果计算了试件的名义应力-应变曲线,给出了压缩过程中孔壁的失效顺序和破坏规律.对块体材料的压缩实验表明,泡沫纯铝是以多个断裂带的形式破坏和吸收能量.
Statistic analysis on the tested Al foam, including cellular size, shape and relative orientation, is performed based on the best-fit ellipse equivalent diameter for the individual cells. It shows that the statistical distribution of cells＇ size and shape follow Gauss distribution at significance level of 0.05. Based on calculating correlation of the images captured before and after deformation, digital image correlation method （DICM） is employed to measure the deformation of the closed-cell aluminum foam under uniaxial compression. The whole-field and part of cells deformation and displacement distribution are presented, and the nominal stress-strain curve of the tested specimen is also obtained by DICM. Experimental results show that the foam absorb large energy during fracture bands initiation and developing.
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2009年第2期250-254,共5页
Journal of Southeast University：Natural Science Edition
基金
国家重点基础研究发展计划(973计划)资助项目(2006CB601201)
国家自然科学基金资助项目(10727201)
关键词
闭孔泡沫铝
孔结构特征统计
单轴压缩
孔结构变形
图像相关方法
closed-cell aluminum foam
statistics on cellular structures
uniaxial compression
cellular deformation
digital image correlation method （DICM）
