Highly efficient Fe separation induced by Fe-containing particle agglomeration in Al-7Si-0.3Mg alloy melt

In this paper, the melt turbulence process was introduced to result in Fe-containing particle agglomeration and achieve highly efficient Fe separation in Al-Si alloy melt. Microstructure analysis, 3D-morphology extraction, X-ray microscopy (μCT) analysis were conducted to discuss the phenomenon and mechanism of Fe-containing particle agglomeration. The experimental results indicate that the Fe-containing particle is suitable for separation due to the high precipitation temperature and particulate morphology. Then, the intervention of rotor stirring greatly promotes collision, adhesion and agglomeration of Fe-containing particles during sedimentation separation. The Fe-containing particle agglomeration showed a maximum diameter of 1650 μm and a 67.67% reduction of Fe were obtained after rotor stirring. When the sedimentation separation is intervened by rotor stirring and argon blowing, the agglomeration effect of Fe-containing particles further promotes. The Fe-containing particle agglomeration shows the maximum size of 1800 μm and a high Fe separation efficiency of 74.46% were obtained. The simultaneously exerting of rotor stirring and argon blowing promotes the formation of agglomeration attached by small Fe-containing particles, which also contributes to higher Fe separation efficiency. These results provided a new sight to achieve high Fe separation efficiency in Al-Si alloy melt by industrially viable methods.