Microstructure Refinement of Al-5Ti-B Grain Refiner with Electromagnetic Energy

The influence of the electromagnetic energy on the microstructure of Al−5Ti−B grain refiner was discussed. In this study, the electromagnetic energy was applied above the liquid phase line temperature. Compared with Al−5Ti−B without electromagnetic energy applied, the experimental results show that the size of secondary particles is reduced and its size distribution becomes more uniform. Simultaneously, the secondary phase particles are uniformly spread in the matrix response to the electromagnetic energy. Moreover, when adding Al−5Ti−B with electromagnetic energy to the pure aluminum melt, it is clear that the electromagnetic energy has a significantly impact on refining properties of Al−5Ti−B. The mean size of pure aluminum is reduced by 27.6% in maximum with more uniform size distribution. The change in the microstructure is attributed to the electromagnetic energy changes the melt structure. With the electromagnetic energy entry into the system, the electromagnetic energy reduces the size of atomic clusters and increases the number of atomic clusters, thus the number of nuclei increases.