溶融Al-10%Fe合金の冷却過程で晶出する初晶Al₁₃Fe₄相の電磁分離

抄録

  In this study, the electromagnetic separation behavior of primary Al₁₃Fe₄ crystallized in the cooling process of molten Al-10%Fe alloy was clarified by observation of the solidification structure. The electromagnetic force was controlled by keeping the magnetic flux density constant and changing the applied direct current. The applied current was set in the range of 0 A to 100 A, and the experiment was conducted at intervals of 20 A to investigate the electromagnetic separation behavior of primary Al₁₃Fe₄.

  During the cooling process, no separation effects of primary Al₁₃Fe₄ were observed, even when current or magnetic field was independently applied. When both the current and magnetic field were applied, primary Al₁₃Fe₄ was miniaturized by the electromagnetic force and distributed in the surface layer of the sample. However, no eutectic Al₁₃Fe₄ separation effect was observed. Even when the direction of the magnetic field was changed, primary Al₁₃Fe₄ was similarly distributed in the surface layer of the sample. Electromagnetic separation effects were observed even in the range beyond the magnetic poles. When the length of the sample was shortened to within the range of the permanent magnet, no change was observed in the distribution behavior of primary Al₁₃Fe₄ in the surface layer of the ingot. During the cooling process, a negative pressure gradient was assumed to be formed from the specimen axis toward the surface, regardless of the direction of the electromagnetic force.