On-Line Detection of Friction Stir Welded Joints by High Temperature Phased Array Ultrasonic Inspection and Control of Weld Process Parameters

Abstract

Non-Destructive Evaluation (NDE) of welded structures is essential in industry and manufacturing sectors. However, NDE techniques are limited when applied at high temperatures, which prevents usefulness for on-line real time inspection of welded joints. In this work, a high temperature (HT) inspection system was created utilizing Phased Array Ultrasonic Testing (PAUT), and tested on Friction Stir (FS) welded aluminum alloy joints. The system created in this work proves HT-PAUT is capable of determining defects during the welding process. Supplementing this work, a custom defect detection software was created to analyze S-Scan data to interpret when and where a defect occurs to provide defect indicator signals. These defect signals can be utilized for controlling the FSW process parameters to automatically correct if a defect is observed. The technology developed can be utilized as a platform for future automated welding processes and control for creating the next generation weld-NDE systems.