悬臂闭孔泡沫铝板的非线性振动实验研究

发布时间：2018-01-23 02:51

本文关键词： 悬臂闭孔泡沫铝板非线性振动模态形状电子散斑干涉　出处：《东南大学学报(自然科学版)》2017年04期 　论文类型：期刊论文

【摘要】：为了研究闭孔泡沫铝板的非线性振动特性,首先采用电子散斑干涉技术对3个孔隙率相同的悬臂闭孔泡沫铝板共振模态进行了测量,获得了前14阶离面共振激励频率和相应的模态振型,并基于欧拉-伯努利梁模型及1阶弯振频率测量值计算得到闭孔泡沫铝的动态弹性模量.然后对相同孔隙率的闭孔泡沫铝静态单轴压缩力学行为进行了实验研究,测得了其静态压缩弹性模量.实验结果表明:由于闭孔泡沫铝存在大量不规则孔洞结构,导致其振动响应具有明显的非线性,表现为同一振动模态对应于数个谐振激励频率,是典型的超谐振.另外,基于振动分析得到的泡沫铝动态弹性模量是静态压缩弹性模量值的2倍多,这与泡沫铝是拉压双弹性模量材料有关.
[Abstract]:In order to study the nonlinear vibration characteristics of closed hole aluminum foam plate, the resonance modes of three cantilever aluminum foam plates with the same porosity were measured by means of electronic speckle interferometry (ESPI). The first 14 off-plane resonance excitation frequencies and the corresponding modal modes are obtained. Based on the Euler-Bernoulli beam model and the first order bending frequency measurement, the dynamic elastic modulus of closed cell aluminum foam was calculated. Then the static uniaxial compressive mechanical behavior of closed cell aluminum foam with the same porosity was studied experimentally. . The static compressive modulus of elasticity is measured. The experimental results show that the vibration response of closed porous aluminum foam is obviously nonlinear due to the existence of a large number of irregular pore structures. The same vibration mode corresponds to several resonant excitation frequencies and is a typical superresonance. In addition, the dynamic elastic modulus of aluminum foam based on vibration analysis is more than 2 times that of static compression elastic modulus. This is related to the fact that aluminum foam is a double elastic modulus material.
【作者单位】：东南大学江苏省工程力学重点实验室;
【基金】：国家自然科学基金资助项目(11272090,11472081,11532005)
【分类号】：TB383.4;TG146.21
【正文快照】： 泡沫铝及泡沫铝合金是一种新型的结构和功能材料,因存在大量孔洞而具有有效的能量吸收及阻尼作用;同时还具有超轻、高比刚度和强韧性等特性,在工程上有广泛的应用前景.例如作为包装工业的吸能器,以及作为夹层板结构的芯材应用在高速列车、轮船和航天器等领域[1-2].目前,国内外

【参考文献】