Comparison between Simulation and Experimental Results of the Effect of RMF on Directional Solidification of Al-7wt.%Si Alloy

Abstract

A numerical investigation of directional solidification of Al-7wt.%Si alloy stirred by a rotating magnetic field is compared with experimental results. Experimental study of such process has revealed periodical macrosegregation in axial direction of the samples in the shape of a “Christmas tree”. Similar macrosegregation pattern is obtained in simulations for the two values of magnetic field. Numerical simulations have shown also that formation of the periodical structure depends not only on the external conditions but on the permeability of the mushy zone.

Numerical modeling of a benchmark experiment on equiaxed solidification of a Sn–Pb alloy with electromagnetic stirring and natural convection

“…Yet, it was also found that strengthened convective flow being structured can provoke even heavier macrosegregation. In laboratory-scale experiments a so-called "fishbone" segregation pattern was observed in solidification under rotating magnetic field [13,14] and promotion of channel formation inside columnar mushy zone with use of travelling magnetic field [15]. In industrial continuous casting, for instance, formation of a centerline defect [16] or a so-called white band [17] were found.…”

Effect of the rotating magnetic field on the unidirectionally solidified macrostructure of Al6Si4Cu alloy

“…It has been stated that the transient phenomena in the macro-and microstructure formed during switch-on and switch-off of the magnetic field are so small that they do not influence significantly the developed macroand microstructure. In the samples solidified with stirring a characteristic macrosegregation developed if the magnetic induction was higher than 10 mT [2][3][4]. The aim of this work was to investigate this macrosegregation and the macrostructure formed in the samples using the suggested new experimental method.…”

Effect of vertical electromagnetic stirring on solute distribution in billet continuous casting process

“…In principle, the R-EMS generates peripheral flow in stirring region while the V-EMS generates longitudinal flow, and combination of R-EMS and L-EMS can produce spiral flow of melt [10][11] . Many theoretical and experimental investigations have been made regarding the effect of R-EMS or L-EMS in continuous casting process [6,[12][13][14][15] . However, multiple industrial examples demonstrate that effect of the EMS depends on actual configuration of the casting process and that of the stirrer, as well as on the positioning of the latter [16,17] .…”