APPLICATION OF ACOUSTIC EMISSION METHOD FOR DETECTING DIFFUSION INTERLAYERS IN DIFFERENT WELDED JOINTS

Abstract

The paper investigates the possibility of detecting specific structural defects of dissimilar welded joints by the method of acoustic emission (AE). Carbide and decarburized interlayers are formed in dissimilar welded joints of austenitic and pearlitic steels during welding and subsequent operation. Diffusion interlayers, as a structural defect, are usually small in size and cannot be detected by traditional non-destructive testing (NDT) methods, while the AE method is promising for detecting such defects. In the present work, we studied the AE data obtained during testing of defect-free specimens of a welded joint and specimens with diffusion interlayers. It has been established that the AE parameters for defective and defect-free welded joints have significant differences, which makes it possible to identify the presence of diffusion interlayers in dissimilar welded joints.