Effect of alternating magnetic field on microstructures and mechanical properties of laser-welded Ti/Fe dissimilar alloy joint.

In this study, fiber laser butt welding was performed on a 6 mm thick Ti-6Al-3Nb-2Zr-1Mo alloy and 10CrNi3MoV steel using two interlayer configurations, with the innovative introduction of an external alternating magnetic field. The microstructure, element distribution, and mechanical properties of the welded joint were investigated through various methods including scanning electron microscopy, energy-dispersive X-ray spectrometer, and X-ray diffraction. Results showed that joints with two interlayer configurations were present in an interfacial layer with non-uniform thickness and poor mechanical properties, due to the heterogeneous heat distribution in the thickness direction and the mixing of elements during the laser welding process. Applying an alternating magnetic field facilitated convection of the molten pool from center to sides, which accelerated forced convection in both vertical and horizontal directions leading to more uniform heat distribution as well as element distribution resulting in a significant reduction or disappearance of unmelted Cu for different interlayers, while also reducing the thickness of the interfacial layer at the upper part of the joint and significantly improving tensile strength by 5.9% and 8.3%, respectively. [ABSTRACT FROM AUTHOR]