纤维断裂损伤对复合材料板中导波频散特性的影响

摘要

利用带状单元法分析了存在纤维断裂损伤的复合材料板中导波的频散特性,并讨论了不同损伤模式对导波频散特性的影响.将纤维增强复合材料板的每一铺层视为一个带状单元,对于纤维断裂铺层,假设材料常数退化成与基体相同.在此假设下,获得了含纤维断裂损伤复合材料板的运动方程,将该方程转化为特征值问题,即可获得板中导波频率与波数的关系.最后利用数值算例分析了单层纤维断裂和多层纤维断裂损伤对导波频散特性的影响,分析结果可对纤维增强复合材料板的超声无损检测技术提供理论依据.%The dispersion characteristic of guided wave in composite plate with fiber fracture damage is analyzed using strip element method,in which the different damage patterns are considered.The layer with fracture damage is assumed to have the same elastic constants as the substrate.Taking each layer as a strip element,the equation governing the movement of a single layer is constructed.Through assembling the governing equations of all layers,the global movement equation of the composite plate with fiber fracture damage is obtained.Rewriting the global equation yields the corresponding eigenvalue problem,which can be used to calculate the relationship between the guided wave frequency and wave number in the plate.Finally,the influence of different damage patterns on the dispersion characteristic of guided wave is investigated by numerical examples.The results may provide theoretical basis for non-destructive evaluation of damage in the fiber-reinforced composite plate via ultrasound technology.