ASSESSMENT OF FRICTION STIR WELD QUALITY BY ANALYZING THE WELD BEAD SURFACE USING BOTH DIGITAL IMAGE PROCESSING AND ACOUSTIC EMISSION TECHNIQUES

摘要

The success of Friction Stir Welding (FSW) depends upon how well the tool shoulder interacts with base material, generating required frictional heat, controlling flow of material to ensure proper containment and consolidation resulting in a defect free weld. In the present work, the weld bead surface of AA6082-T6 specimens produced by shoulders of different geometry (Flat and Concentric rings) with selected welding parameters are assessed by using digital image processing. The images of the weld bead surface are captured, processed, and analyzed by extracting first and second order statistical image parameters along good and defect weld regions in comparison with X-Ray Radiography. The variations in statistical image parameters of weld bead images are observed, enabling digital image correlation to assess weld quality. The results obtained are also verified by Acoustic Emission (AE) data acquired during FSW, showing variations similar to that of image data along good and defect weld regions.