Numerical simulation of electromagnetic DC casting of magnesium alloys

The flow pattern and temperature field of direct chill (DC) casting of magnesium alloys with and without electromagnetic (EM) fields were studied by numerical simulation. The results reveal that the vortex agitation produced by EM field reduces the temperature gradient and shallows liquid sump depth during DC casting, and the surface quality of the billet could be improved owing to the lower contact pressure between the solidification skull and graphite annulus affected by Lorentz force. Lower AC frequency enhances the depth of penetration of electromagnetic field and higher AC current intensity intensifies vortex agitation. Casting velocity influences the flow pattern and temperature field as well as the valid operation time of the EM field.