Effect of low-frequency magnetic field on microstructures of horizontal direct chill casting 2024 aluminum alloy

The horizontal direct chill (HDC) casting process is a well-established production route for aluminum alloy ingots but the ingot may some times suffer from inhomogeneous microstructures due to unbalanced cooling and the effect of gravity. In order to control the defect, a low-frequency electromagnetic field has been applied in HDC casting process and its influence has been studied. The results show that a low-frequency electromagnetic field can effectively reduce inhomogeneous microstructures in HDC castings. Two main parameters of the electromagnetic field-density and frequency, significantly influence the microstructures and solution distribution along the diameter of the ingot. The mechanisms of the effects of electromagnetic field have been discussed.