考虑胶层的蜂窝夹层复合材料动态特性

Dynamic characteristics of honeycomb sandwich composite considering effect of adhesive layer

提出了一种蜂窝夹层复合材料等效模拟方法.将面板与胶层等效为层合材料,并推导了其等效弹性参数.根据等效板理论、三明治夹芯板理论及所提出的方法分别建立自由-自由状态的铝蜂窝夹层复合材料有限元模型.将3种等效方法的数值计算结果与试验模态参数进行对比,结果表明,所提出等效方法的最大误差不超过5%,平均误差降低到2.03%,表明考虑胶层的影响,模态参数计算结果更为精确.通过控制变量法和相对灵敏度分析表明,胶层是影响复合材料动力学性能的关键因素之一,在面板与蜂窝胞壁连接良好的前提下,减小胶层的厚度或增加胶层材料的弹性模量能够有效提升材料的整体动态性能.

A new method for equivalent numerical modeling of honeycomb composite is proposed in this paper. The face sheet and the adhesive layer are equivalent to a laminated material, and the expressions of equivalent elasticity of the multilayered material are derived. Three equivalent methods, including the equivalent plate theory, the sandwich theory and the presented method, are respectively used for model the honeycomb sandwich plate under the free-free condition. According to the comparison between the numerical predictions and the experimental modal parameters, it is found that the precision of computational modal data of the presented method is improved. The maximum error is no more than 5 %, and the mean value of errors is decreased to 2.03 %, showing that considers the influence of adhesive layer makes the result more accurate. The variable-controlling approach and relative sensitivity analysis are employed to compare the impact on dynamic characteristics between parameters of the adhesive layer and the other parameters in the honeycomb composite. Results indicate that parameters of the adhesive layer are the key factors affecting the dynamic characteristics of the honeycomb composite. When the face sheet and the cell wall of the honeycomb are well-connected, decreasing the thickness or increasing the elastic moduli of the adhesive layer can improve the dynamics performance of the composite effectively.