Change in the structure of the aluminium alloy under the action of direct electric current

Abstract

The capabilities of the method for producing cast aluminum alloys, including composite alloys, which include the transmission of direct electric current at the crystallization stage, are shown, and the results are studied for experiments on the crystallization of aluminum alloy (silumin: Si – 10.47 %; Cu – 1.75 %; Fe – <0.2 %; Cr – 0,.02%; Mg – <0.02; Mn – <0.02 %; Ni – 0.08 %) under the action of direct electric current. Comparative study of the structure and porosity of the aluminum alloy, the crystallization of which occurred under the influence of electric current and without current, showed that the electric current leads to a change in the structure of the alloy, reducing porosity, creating a finely differentiated eutectic with a decrease in the dendritic parameter.The mechanism of influence of electric current on the movement of inclusions in the melt is based on the diffusion process. Within the framework of considering the diffusion flux created by the electric field of the current, the speed of the inclusion of crystalline silicon in the melt was calculated in a linear approximation, which shows the possibility of applying this effect in obtaining aluminum matrix composite materials.