超声底波成像方法研究

针对超声缺陷波成像检测的盲区问题,研究了利用超声底部回波信号进行成像的方法。采用缺陷波幅值成像、缺陷波深度成像和底波幅值成像三种成像方式对ZGS对比试块上的9个不同深度的2 mm平底孔进行了检测。对比试验表明,超声底波成像方法可用较低的系统增益检测出缺陷,也能检测出用缺陷波幅值成像方法时近表面盲区部位的缺陷,是缺陷信号幅值成像方法的有效补充。

Study on Ultrasonic Imaging With Bottom Echo

To improve the system gain and eliminate the dead zone in ultrasonic imaging testing, the method of ultrasonic imaging testing with bottom echo amplitude was studied. Comparative experiments were carried out on ZGS reference block to test the 9 flat bottom holes(FBH) with different depths by three imaging methods i.e. the ultrasonic defect echo amplitude imaging method, the ultrasonic defect echo depth imaging method and the ultrasonic bottom echo imaging method. It was shown by the experimental results that all the 9 FBHs were found with lower system gain by ultrasonic bottom echo imaging method, especially those sub-surface ones in the dead zone when using ultrasonic defect echo amplitude imaging method. It was proved that the ultrasonic bottom echo imaging method was a feasible and effective complement for the ultrasonic defect echo amplitude imaging method.