高度方向尺寸对铝蜂窝面外力学性能的影响

Effects of Specimen Height on the Mechanical Behavior of Honeycomb in Out-of-plane

对10种不同高度的正六边形商用铝蜂窝进行了加载速率为6 mm/min的面外单轴压缩实验,以此来确定高度方向的尺寸对铝蜂窝力学性能(曲线模量、弹性模量、峰值应力、平台应力以及密实化应变)的影响,并对各尺寸试样的力学性能进行了比较。实验结果表明:铝蜂窝试样高度方向的尺寸对其峰值应力、以及平台应力几乎没有影响,但是密实化应变和弹性模量对蜂窝试样的高度方向的尺寸是敏感的,并且均随H/d增大而增大,对于密实化应变在H/d>3.46时趋于稳定,而高度尺寸直到H/d>4.16对弹性模量的影响才消失。其中H为蜂窝试样高度方向的尺寸,d是蜂窝细胞的尺寸。为了获得铝蜂窝结构稳定的力学参数,蜂窝试样高度尺寸与其胞元尺寸的比值至少应大于4.16。

Out-of-plane compression tests are applied on ten kinds of commercial aluminum hexagonal honey- comb specimens with different height values to study the effects of specimen height on the mechanical behaviors （curve modulus, elastic modulus, peak stress, plateau stress and densification strain） of honeycomb. Results show that the height of specimen almost has no effect on peak stress and plateau stress. However, the elastic modulus and densification strain are sensitive to the height of honeycomb specimen. In addition, both the two parameters are incresae as the height increases. And the elastic modulus become stable until H/d〉 3.46 while the densification strain show height independent as H/d 〉 3.46. In a word, the H/d 〉 4. 16 is needed to obtain the effective me- chanical properties of a bulk sample of honeycomb.