Research and Proposal on Welding Technique for Longitudinal Crack Defect Welding

Abstract

Manufacturing of intentional crack defect welding as designed and similar to realistic crack defects for researches of mechanical properties of welding and training of non-destructive testing (NDT) operator is a difficult and challenging work. Nowadays, methods for manufacturing of specimens of welding with cracking defect still exists some disadvantages such as difficulty in manufacturing, reactionless of the cracks to NDT techniques, the difference between the crack shape and that in nature, and high cost, etc. In this research, we propose a new approach to create welding crack with residual stress using cast iron electrodes. The process to create the welding cracks based on this technology using the SMAW combining with GTAW allows to create the welding with cracks similar to those in nature. Cracks are created with lateral deviation not more than ± 0.5 mm, well response to the phased array ultrasonic testing technique and have similar shape to natural shape of the crack defect.