Research On Iron Removal Of Aluminum Melt

Iron removal has been a global problem that hinders the development of aluminum industry. It is crucial to the expansion of raw material application and improvement of production quality in aluminum industry.In this paper, two kinds of methods have been designed to remove iron. The first kind was using the borides to remove iron which was called chemical method. The element B in the borides, which were added into the aluminum alloy, would react with Fe and form a kind of high melting point compound, and the big density compound can sink in the bottom of furnace with slag. So the impurity Fe can be removed from the aluminum melt. With regard to Al-wt5%Fe alloy, when adding a little B2O3 or Na2B4O7, CFe declined with a certain extent. The reduction of CFe came to the dramatic when adding 7%B2O3. And CFe increasingly reduced with the extension of time, it achieved the lowest 2wt%after 90min. When adding 7.5% Na2B4O7, the reduction of CFe came to 2.1wt%after 90min. However, when the addition continued to increase, CFe didn't change obviously.Another kind was electromagnetic separating iron-rich phases from aluminum melt which was called physical method. Most of impurity Fe existed in the kind of iron-rich phase in the aluminum alloy. By using the big difference in the electric conductivity between the iron-rich phases and aluminum liquid, the micro-grade iron-rich phases were removed from the aluminum melt. The separation effect for the aluminum alloy sample under different separation time was studied in the experiment. When the separation time increased, more and more iron-rich phases would transfer from the center to the outer region. When the separation time was 60s, most of the ron-rich phases were removed to the edge of the sample and distributed evenly. When the time increased continuously, the iron-rich phases which had been removed would return to the center because of the turbulence which was caused by induction heat, and it affected the experimental result badly. So the time of 60s was the best separation time.The other non-metallic inclusions are also removed from aluminum melt by using electromagnetic separating technology in this paper, and the experiment result is good.