Formation of twinned lamellas with the application of static magnetic fields during semi-continuous casting of Al–0.24wt%Fe alloy

Influence of Cr on the nucleation of primary Al and formation of twinned dendrites in Al–Zn–Cr alloys: Can icosahedral solid clusters play a role?

“…These complex intermetallics formed under equilibrium conditions can coexist together with iQCs in rapidly solidified Al-Cr alloys when there is insufficient time for long range ordering [21,39,46]. Also in AlZn-Cr alloys, an intermetallics phase, Zn 13 (Cr x Al 1-x ) 27 (x = 0.34-0.37), has been recently reported which has icosahedral building blocks in its rhombohedral structure [47]. Therefore, the existence of the complex Al 45 Cr 7 and Zn 13 (Cr x Al 1-x ) 27 (x = 0.34-0.37) intermetallic phases at equilibrium is also an indication of the tendency to form icosahedral ordering in Al-20%Zn-0.1%Cr alloy.…”

“…However, the role of convection is still unclear. More confusion has been brought recently by Li et al [13], who observed that the application of a static magnetic field of only 0.2 T, which is supposed to weaken convection, induces the formation of twinned dendrites in Al-Fe and Al-Zn alloys in small DC cast ingots. Finally, although twinned dendrites have a growth advantage over regular dendrites under the above-mentioned conditions, there is still some uncertainty about their tip morphology [3,12,[14][15][16][17][18].…”

Improvement of AA5052 sheet properties by electromagnetic twin-roll casting

“…They found that the microstructure formation depends on the frequency of the applied alternating current and that it changes spontaneously as the alternating electric field is applied. Li et al [14,15] investigated semi-continuous casting of Al alloy with the application of a static magnetic field. They found that the static magnetic field changes the microstructure from regular columnar grains to twinned lamellas.…”

Influence of a high magnetic field on the precipitation behavior of the primary Al3Fe phase during the solidification of a hypereutectic Al-3.31wt% Fe alloy

“…However, the microstructural modification capacities of the two types of fields are different. As the intensity of the conventional magnetic field is low, its effect on the structures of non-magnetic alloys mainly results from Lorentz force, which is involved in suppressing [1][2][3][4] and driving [5][6][7] the fluid. Whereas under a high magnetic field, besides the Lorentz force, this increased field enhances the magnetization force that is usually negligible in the conventional magnetic field.…”