全聚焦法焊缝检测灵敏度特性

全聚焦法(TFM)是用后处理算法增强的超声技术.基于全矩阵捕获(FMC)采集数据,由TFM生成的图像几乎聚焦在每个像素上,因而能提高缺陷检出率,改善缺陷定量和表征技术.本文评析焊缝检测中某些方向性面型缺陷引起的信号波幅变化,并对此与其他技术——超声相控阵检测(PAUT)、射线检测(RT)和金相检测结果作了比较.强调声传...

Sensitivity Characteristics of Total Focusing Method for Weld Inspection

The Total Focusing Method(TFM)is an ultrasonic-based technique enhanced with the postprocessing algorithm.Based on the data acquisition in Full Matrix Capture(FMC),TFM creates an image nearly focused at every pixel.Hence it can increase the detectability of flaws and improve their measuring and characterization techniques.This article will analyze the amplitude variation caused by some directional planar defects and compare it with other techniques,such as phased array ultrasonic testing(PAUT),radiographic testing(RT)and metallographic test.It is emphasized the importance of TFM imaging quality of planar defects affected by the appropriate choice of the acoustic propagation mode.Finally,some other factors influencing the sensitivity response of TFM technique are still discussed.