基于Lamb波递归量化分析的复合材料裂纹损伤定征研究

以谐波激励下的不同损伤引起的结构非线性特性为基础,利用递归量化分析对复合材料的基体微裂纹损伤进行量化检测。以不同外载条件下产生的不同裂纹损伤的复合材料层合板为试验对象,对靠近损伤区域的路径中的Lamb波信号进行了递归图的分析绘制,在此基础上采用递归量化指数对各路信号包含的损伤信息进行了定量表征;为了达到对损伤统一表征的目的,以特征向量间的欧式距离作为损伤状态相对于无损状态的偏离程度,建立了统一损伤指数。分析结果表明该研究提出的统一损伤指数对复合材料基体微裂纹损伤具有较好的敏感性,并随损伤程度增加成良好的线性递增趋势,其为复合材料的基体微裂纹损伤定征提供了一个有效可行的方法与手段。

Crack damage investigation of composite materials based on theLamb wave and recursive quantitative analysis

Based on the nonlinear structure characteristics caused by different defects under harmonic excitation,the recursive quantitative analysis(RQA)was used to quantify the damage of matrix microcracks in composite materials.The composite laminates with different crack damages under different external loads were taken as the test object,and the Lamb wave signals in the path near the damage region were analyzed with recursive plots and quantitatively characterized with RQA parameters.Based on the Euclidean distance between RQA eigenvectors,a united damage index(UDI)was proposed to quantify the deviation of damage state relative to intact state.The experimental analysis verified that the proposed UDT has the sensibility to the matrix microcracks and linearly increases with the damage degree.It could be used as an effective and feasible method for quantitatively evaluating the matrix micro cracks in composite laminates.