Microstructure and properties of Al-Si alloys under intermediate frequency electromagnetic field

Abstract

The intermediate frequency electromagnetic (IFEM) field was applied to treat Al-1%Si (high-purity) and Al-8%Si alloys during direct chill (DC) casting process. The ingot was studied by means of metallographic examination and mechanical tests. The results showed that compared to the conventional casting, both Al-1%Si and Al-8%Si alloys processed under IFEM field exhibited superior refinement as well as an enhancement in the mechanical properties, especially the elongation. Si element segregation of high purity Al-1%Si alloy had effectively improved under IFEM field. Numerical simulation was used to better understand the role of IFEM field, that showed the inducing forced convection and the subsequent achievement of a uniform temperature field of IFEM field during the solidification could be accounted for the experimental observations.