柱胞夹芯复合材料承载/减振性能研究

Bearing and damping performance of column-cell sandwich composites

设计一种以薄壁球壳作为复合材料芯子的柱胞夹芯复合材料,研究其结构承载能力和阻尼减振性能一体化的特性。进行2×2柱胞排列的柱胞夹芯复合材料准静载压缩实验和3×7柱胞排列的振动测试实验,并通过有限元模拟静载压缩实验和模态分析。结果表明:随着球壳直径的增大,发生翻转和非对称屈曲所需要的临界位移增大;压缩相同的位移,直径小的球壳压缩荷载大,不锈钢薄壁椭球壳最大应力较高,较紫铜易于屈服,其振动频率较高,结构承载能力强,阻尼减振能力强于紫铜。随着球壳壁厚的增加,承载能力逐渐增强,阻尼比呈先增后减的趋势,以直径较大的球壳为芯子的柱胞夹芯复合材料阻尼减振性能高于小直径球壳。

A new sandwich composite in which core was arranged in thin-walled shells was designed. The characteristics of the integration of the structural bearing capacity and damping performance were studied. The static load compression experiment that spherical shell element was arranged in 2~ 2 mode and vibration experiment that shell element was arranged in 3 ~7 mode was carried out, and the static compression experiment and modal analysis were simulated by means of finite element. The results show that the critical displacement of flipping and asymmetric buckling increases as the diameter increases. When compressing the same displacement, small diameter shell requires a large compression force. The maximum stress of stainless steel shell is higher, and it is easier to yield compared with copper. Its vibration frequency is higher, the structure bearing capacity is stronger, the damping capacity is superior than that of copper. With the increase of wall thickness of spherical shell, the bearing capacity gradually increases, the damping ratio increases first and then decreases, the damping performance of the sandwich composite with larger diameter spherical shell is higher than that of the small diameter spherical shell.