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研究使用低频多模式超声兰姆波估计超薄层状横观各向同性复合材料的弹性常数、密度和厚度等参数的方法。这里“超薄”的概念是指材料厚度远小于材料中的声波波长，导致在时域上材料前后界面的各次回波信号相互混迭。文章分析了沿平行和垂直于纤维两种方向上，在超薄层状横观各向同性复合材料中传播的低频兰姆波的色散特性，提出在最小二乘意义下以材料多模式兰姆波色散曲线为基础的反向算法对材料进行了参数估计．文中分析了影响估计准确性的各种因素，研究了方法对材料各参数的灵敏度及其在误差传递中的意义，建立了评判反演材料参数准确度的理论依据。结合超声泄漏兰姆波频域分析方法并使用超声耦合剂耦合方式和一对中心频率为 ２ＭＨｚ的宽带纵波换能器，实验结果证实该方法能够准确估计的单向玻璃纤维增强聚醚砜（ＰＥＳ）的材料参数．
The method to estimate the elastic constant, density and thickness of ultrathin layered transversely isotropic composites by using low frequency multimode ultrasound Lamb wave was studied. Here, the concept of “thinness” means that the thickness of the material is much smaller than the wavelength of the acoustic wave in the material, resulting in the mutual overlapping of the signals of the front and the back of the material in the time domain. In this paper, the dispersion characteristics of low frequency Lamb waves propagating in ultrathin layered transversely isotropic composites parallel and perpendicular to the fiber are analyzed. In the sense of least square, the multimode Lambam Dispersion curve based on the reverse algorithm for the material parameters were estimated. In this paper, various factors affecting the accuracy of the estimation are analyzed, the sensitivity of the method to the parameters of the material and its significance in the error transfer are studied, and the theoretical basis for the accuracy of the material parameters inversion is established. Combined with the method of ultrasonic leakage Lamb wave frequency domain analysis and the use of ultrasonic coupling agent coupled with a pair of wideband longitudinal wave transducers with a center frequency of 2MHz, the experimental results confirm that the method can accurately estimate the unidirectional glass fiber reinforced polyethersulfone (PES ) Of the material parameters.