Characteristics of miab welding process and joints

The paper presents the MIAB welding of thin walled tubes achieved with an original longitudinal magnetization system, designed to assure the magnetic flux concentration on the tube wall. Based on images resulting from process monitoring, the main stages of the process are presented, starting with arc initiation, to apparition of molten metal, upsetting and ending with the weld achievement. Infrared thermography was also used for temperature measurements and visualization of the process. Macro and microstructural analyses accompany the hardness tests made on correspondingly welded samples, demonstrating the process capability in producing sound joints when guided by the operational windows developed through this investigation.