Effects of Traveling Magnetic Field on Interfacial Microstructure and Mechanical Properties of Al/Mg Bimetals Prepared by Compound Casting

In this work, the Al/Mg bimetals were prepared by traveling magnetic field (TMF)-assisted compound casting, and the effects of current intensity on the interfacial microstructure and mechanical properties of the Al/Mg bimetals were investigated. The results revealed that the Al/Mg bimetallic interface without the TMF consisted of an Al-Mg intermetallic compounds (IMCs) area (Al₃Mg₂ + Al₁₂Mg₁₇ + Mg₂Si particles) and Al-Mg eutectic area (Al₁₂Mg₁₇ + δ-Mg). There was no change in the interfacial phase compositions with the TMF, but the interface thickness initially decreased and then increased with the increase in the TMF current, and the distribution of Mg₂Si became more uniform, dendrites become smaller, and dendritic arms fragment. The shear strength improves from 17 MPa without the TMF to 27 MPa with the TMFed-60 A, which was increased by 58.8%. This enhancement occurs because cracks are deflected by uniformly distributed Mg₂Si particles and do not coalesce into main cracks, ultimately fracturing in the eutectic region, which increases the length of the crack propagation path and thereby improves the shear strength of the Al/Mg bimetals.