Sectorial Plane Wave Imaging for Weld Inspection Studies

Advanced ultrasonic array–based imaging techniques that rely on A-scan data acquired through individual parallel reception of array elements and subsequent post-processing have shown promising performance by generating high-resolution images. An advanced array-based imaging algorithm called sectorial plane wave imaging (SPWI) has been recently proposed with multimode imaging and rapid inspection capabilities. In this work, the efficiency of the SPWI algorithm is demonstrated and compared to the total focusing method (TFM) and plane wave imaging (PWI) algorithms in detecting different types of common weld defects: lack of sidewall fusion, slag, porosity, toe crack, centerline crack, and root crack. The full matrix capture data acquired over each weld defect using a 32-element linear array on an angular wedge configuration is converted to the PWI matrix data to perform SPWI. The corner and indirect mode SPWI inspection results are able to detect all the weld defects with image quality comparable to that of TFM and PWI, but at a higher processing speed due to the slight compromise over reception focusing, making SPWI a viable advanced ultrasonic array–based imaging technique for inspecting welds.