航空制件超声检测中的声场特性分析

Character Analysis for Acoustic Field in Ultrasonic Testing of Aeronautical Products

针对航空制件超声检测中影响缺陷定量准确性的声场问题进行了深入讨论 ,研究了脉冲波声场的计算方法 ,设计了相应的计算软件并绘制出实用换能器声轴线上的声压分布曲线 ,分析了不同材料和厚度的采样回波对频谱的影响 ,比较了连续波声场和脉冲波声场的分布特性及异同点。

In this paper, the acoustic field character of the ultrasonic pulse wave in ultrasonic testing of aeronautical products is deeply discussed. It is known that the field character influences greatly the measurement accuracy of flaw equivalent in the testing. The method of calculating the acoustic field of pulse ultrasonic wave is researched and the relative special-purpose software is designed; the distribution of acoustic pressure on the axis of the commercial ultrasonic transducer is calculated and plotted by use of computer and the software. It is discussed how the spectrum of the bottom echoes is influenced by materials and thickness. The acoustic field character of the pulse wave radiated by the commercial transducer is compared with that of an ideal continuous mono-frequency wave. The results provide the scientific basis for improvements of the measurement accuracy of the flaw equivalent in ultrasonic testing.