电磁分离降低铝硅合金中铁含量

Reducing Iron Content in Al-Si Alloy by Electromagnetic Separation

利用电磁分离法去除铝熔体中初生富铁相 ,以降低合金中铁含量 ,并在自制电磁分离实验装置上对 Al- 1 2 % Si- 1 .1 % Fe- 1 .2 % Mn熔体进行连续电磁分离 .结果表明 ,经过一次电磁分离使熔体中 >1 0μm的初生富铁相全部去除 ,铁含量从 1 .1 3 %降低到 0 .6 7% ,而处理后的合金重熔凝固后仍然形成大量初生富铁相 ,再次进行电磁分离处理则使铁含量进一步降低到 0 .41 % .Fe在铝熔体中扩散和富铁相的凝固特性决定了需要两次以上电磁分离才能有效地降低合金中铁含量 。

In order to reduce the iron content in Al-Si alloy, removing primary iron-rich phases from the melt was proposed in electromagnetic field induced by static magnetic field and DC current. The principle of this method is that electromagnetic force scarcely acts on iron-rich phases so that the phases are compelled to one side of the separator and captured when the melt flows through the separator. The electromagnetic separation experiments of Al-12% Si-1.1% Fe-1.2% Mn melt were done on a self-designed separation equipment. It indicates that primary iron-rich phases larger than 10 μm have been removed successfully from the melt and the iron content has been reduced from 1.13% to 0.67%. Many primary iron-rich phases are found in the processed alloy after it is remelted and solidified. After the processed alloy is remelted and processed by electromagnetic separation again, the iron content is further reduced to 0.41%. It is determined by these characteristics of the diffusion of Fe and the formation of iron-rich phases in the melt that two or more times of electromagnetic separation are needed to reduce the iron content efficiently which can meet the industry demand of Al-Si alloys.