Experimental Investigations on Magnetically Impelled Arc Butt Welded T91 Steel Tubes

摘要

Magnetically impelled arc butt welding (MIAB) is said to be a hybrid solid-state welding technique which is mainly preferred for butt welding of hollow cylindrical parts such as pipes and tubes. The MIAB setup is robust and fairly simple in design, and requires low upset pressure than the methods like Friction welding. This study investigates the effect of MIAB welding parameters on T91 steel tubes and the experimental observations on the welded joints. The input parameters considered in the present work are welding current (900, 1000, 1100 A), tube thickness (3.5, 4.5, 5.5 mm) and weld time (6, 9, 12 s). The tensile strength and hardness measurements have been recorded and the cross sectional micro and macro images have been observed for the welded samples. Further, the welded specimens have undergone computed tomography and radiography tests. It is concluded from the study that MIAB is one of the feasible welding techniques for joining steel tubes. However, the result shows crack in the weld zone for selected parameters. This defect may be avoided by selecting the optimum welding parameters.