激光与光电子学进展, 2016, 53 (3): 031402, 网络出版: 2016-03-04
双层层压材料中激光超声检测方法的应用
Application of Laser Ultrasonic Detection Method for Double-Layer Laminated Material
激光光学 激光超声 损伤成像 波数分析 层压材料 傅里叶变换 laser optics laser ultrasonic damage visualization wavenumber analysis laminated material Fourier transformation
摘要
为了有效地检测双层层压复合材料中损伤的位置及其形状,提出了一种基于波数分析的激光超声损伤检测方法。在声场互易假设的基础上实现了波场可视化;分析了损伤对材料中超声波波数的影响;采用短空间傅里叶变换的方法,通过时域和频域的局部波数估计算法实现双层层压复合材料的损伤的定位成像;为了充分利用不同时刻和不同频率下的波场信息,减弱时间和频率选取对损伤成像产生的影响,采用了一种波数滤波损伤成像算法,通过对不同时刻的波场进行波数分析,根据不同波数所占的权值不同,采用波数域内加窗的方法滤除健康信号,并通过二维能量图实现损伤的定位成像。
Abstract
In order to evaluate the position and the shape of the damage in double- layer laminated compositematerial, a method of laser ultrasonic damage detection based on wavenumber analysis is presented. Wavefieldvisualization is realized by sound field reciprocity hypothesis. The impact of damage on the wavenumber ofultrasonicis analyzed. Local wavenumber estimation in both time and frequency domain is used, which can makethe damage visible by short-space Fourier transformation. In order to make full use of the wavefield informationat different time and different frequencies, a method based on wavenumber filtering is used. The method can reducethe influence on damage visualization, which is caused by the selected time or frequency. Wavenumber analysis isused for wavefield at different time in this method. Therefore, healthy signal is filtered by window function inwavenumber domain according to the weight of different wavenumbers. As a consequence,damage visualization isrealized by using two-dimensional energy diagram.
朱倩, 裘进浩, 张超, 季宏丽. 双层层压材料中激光超声检测方法的应用[J]. 激光与光电子学进展, 2016, 53(3): 031402. Zhu Qian, Qiu Jinhao, Zhang Chao, Ji Hongli. Application of Laser Ultrasonic Detection Method for Double-Layer Laminated Material[J]. Laser & Optoelectronics Progress, 2016, 53(3): 031402.