1 Institute of Continuous Media Mechanics (Ural Branch of Russian Academy of Sciences), Perm, Russia

S. Yu. Khripchenko, Leading Researcher, e-mail: sk@icmm.ru
V. M. Dolgikh, Senior Researcher
S. A. Denisov, Senior Researcher
I. V. Kolesnichenko, Researcher
L. V. Nikulin, Senior Researcher

Magnetohydrodynamic (MHD) effects on the structure and properties of aluminum alloy ingots are studied. The paper addresses the problems associated with macrostructure identification, assessment of crystalline area dimensions, determination of grain hardness and number in the control area in the center of ingot, and evaluation of the non-uniform distribution of alloying elements throughout the height of ingots and along their radius are solved. The MHD-processing technique for melts implies that the rotating and traveling magnetic fields can be applied separately and in combination. The velocity and kinetic characteristics of the flow excited by magnetic fields have been calculated. Based on the experimental results, the curves for the dependence of crystalline area dimensions, grain hardness and number on the way of applying varying magnetic fields and on the magnitude of the excitation current on inductors have been plotted. It turns out that the optimal mode is a combination of rotating and traveling magnetic fields. When the direction of melt flows is reversed, the alloy components are redistributed throughout the height of ingots and along their radius. The occurrence of grain refinement and nondendritic structure formation is shown. It has been found that the elimination of dendritic structures and grain refinement improve the quality of foundry alloys and increase the deformability of ingots during the fabrication process. A new technique for controlling the granular structure of ingots can be used to prepare melts for plastic deformation and to fabricate cast products.

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