基于一种新型激光干涉仪,测量分析了换能器表面的振动状态。用多路探测单元激光干涉仪获得换能器二维表面上各点的振动波形,对工作性能差异较大的三个换能器(中心频率分别为2.25、5、10 MHz)进行对比。根据测得的换能器表面振动波形,利用有限元方法对超声检测中的回波信号进行定量计算,并将计算结果与实验结果进行对比。结果表明,激光干涉仪可直观、定量表征超声换能器的表面振动状态,并能清晰区分超声换能器工作性能的差异,测量结果对评判超声换能器性能、预测超声检测回波信号具有很好的应用价值。

Based on a new laser interferometer, the vibration state of transducer surface is measured and analyzed. The vibration waveforms of each point on the two-dimensional surface of the transducer are obtained by using a multi-channel detection unit laser interferometer. Three transducers (the center frequencies are 2.25, 5, 10 MHz) with large differences in performance are compared subsequently. According to the measured surface vibration waveform of transducer, the echo signal in ultrasonic testing is quantitatively calculated by finite element method, and the calculated results are compared with the experimental results. The results show that the laser interferometer can directly and quantitatively characterize the surface vibration state of ultrasonic transducer, and can clearly distinguish the working performance difference of ultrasonic transducer. The measurement results have a good application value for evaluating the performance of ultrasonic transducer and predicting the echo signal of ultrasonic testing.