超声回波信号检测橡胶薄层的特性

Testing of Characteristic of Rubber Thin Layer by Ultrasonic Echo Signal

利用超声回波检测法对橡胶薄层特性进行研究,并对频谱分析测量薄层介质特性的理论进行推导,建立有橡胶薄层和无橡胶薄层的回波信号频谱比值的恢复函数H(f)。结果表明,恢复函数H(f)包含着橡胶薄层材料与基体的特性信息,对其进行解析不但可以获得超声波在橡胶薄层中的传播速度,还可以得出薄层的密度及其弹性模量,而且与时频复合域分析方法计算的结果相一致,利用该方法可在不损坏薄层材料的使用性能前提下对其特性进行检测。

With ultrasonic echo testing method, the characteristic of rubber thin layer is investigated. The theory of surveying the thin layer medium characteristic with frequency spectral analysis is deduced. A method is proposed to establish restoration function of frequency spectrum ratio of ultrasonic echoes under the condition of substrate material covered and uncovered with the rubber thin layer. The results show that H（f） contains information on the acoustic properties of the substrate and the thin layer, not only the supersonic wave propagation velocity in the rubber thin layer can be acquired, but also the acoustic impedance of thin layer and density. This method can test the characteristic of the thin layer material without damaging its service performance, the results of which accord with the time frequency composite field analysis method.