中文摘要：

针对金属-非金属多层胶结结构试件中的超声检测回波信号,提出了一种基于小波变换提取特征参数的方法,提取出来的特征用来评估试件的粘接特性.在利用超声信号进行金属-非金属多层胶结结构的无损评价时,各层的超声检测回波会严重混迭,难以分辨甚至会丢失某一层的缺陷信息.使用基于此测试系统脉冲响应的母小波作为基函数来进行小波变换和特征提取,结果显示,提取出的特征可有效地进行备层粘接情况的分析和识别.实验检测结果表明特征提取方法可用在金属-非金属多层胶结结构的无损检测中.

英文摘要：

Presents a wavelet- based approach for extracting features from ultrssonic non- destructive evaluation data of a test multi - layered bonded structure specimen. These features are then used to obtain an estimate of the specimen adhesive properties. When the specimen undergo ultrasonic non - destructive evaluation, echoes from interior layers often overlap severely, causing information from individual layers to be obscured or lost completely. A complex - valued mother wavelet based on the impulse response of the testing instrumentation system is used to perform the wavelet transform and separate the overlapped echoes. The extracted features are effective to analyze and identify the bonded properties. It is believed that the features extracted which via the method outlined provides considerable promise in the area of the test of multi - layered bonded structure.