Abstract: This study investigates the effects of the upward traveling wave magnetic field（TMF）operating at different frequencies on the solidification process,microstructure refinement,and mechanical properties of an Al-7 wt.%Si binary alloy.The alloy solidification samples were prepared using an electromagnetic casting device.A magneticflow-thermal multi-field coupling model was employed for numerical simulation of the melt solidification process,calculating the forced convection and liquid phase distribution within the Al-7 wt.% Si alloy melt subjected to TMF treatment.The results indicate that under 75A 12 Hz-TMF,the peak velocity of the flow field within the Al-7 wt.% Si alloy melt reached 0.023m/s.Under the combined effects of forced convection and Joule heating,the dendrite arm spacing（DAS）of the samples treated at 8 Hz-TMF was refined to 127.8μm.Meanwhile,the ultimate tensile strength and elongation after fracture increased from 100.8 MPa and 6.9%（natural solidification,NMF）to113.7 MPa and 8.3%.When the TMF frequency was increased to 12 Hz,the Joule heating generated within the melt gradually increased,leading to a reduction in the temperature gradient during the solidification process,thereby slowing down the solidification rate of the castings,and the refinement effect on the solidification structure decreased,with the average DAS increasing to 140.3μm,and the mechanical properties consequently degraded.The results demonstrate that the convection induced by TMF and Joule heating are the primary reasons for the refinement of the solidification microstructure and the enhancement of mechanical properties.These findings provide a theoretical basis for the research on improving the quality and mechanical properties of castings through applied electromagnetic field casting technology.