EBSD Study of the Influence of a High Magnetic Field on the Microstructure and Orientation of the Al-Si Eutectic During Directional Solidification

Abstract

International audienceThe effect of a high magnetic field on the morphology of the Al-Si eutectic was investigated using EBSD technology. The results revealed that the application of the magnetic field modified the morphology of the Al-Si eutectic significantly. Indeed, the magnetic field destroyed the coupled growth of the Al-Si eutectic and caused the formation of the divorced alpha-Al and Si dendrites at low growth speeds (a parts per thousand currency sign1 mu m/s). The magnetic field was also found to refine the eutectic grains and reduce the eutectic spacing at the initial growth stage. Moreover, the magnetic field caused the occurrence of the columnar-to-equiaxed transition of the alpha-Al phase in the Al-Si eutectic. The abovementioned effects were enhanced as the magnetic field increased. This result should be attributed to the magnetic field restraining the interdiffusion of Si and Al atoms in liquid ahead of the liquid/solid interface and the thermoelectric magnetic force acting on the eutectic lamellae under the magnetic field. (C) The Minerals, Metals & Materials Society and ASM International 201

Influence of External Static Magnetic Fields on Properties of Metallic Functional Materials

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Effect of Solidification on Microstructure and Properties of FeCoNi(AlSi)0.2 High-Entropy Alloy Under Strong Static Magnetic Field

“…As a clean, non-contact and high-density energy, the magnetic field can act on the atomic scale of substances. As a result, it brings many unique impacts to the material processing, e.g., levitation [ 12 ], nucleation [ 13 ], phase transition thermodynamics [ 14 , 15 ], texturing and orientation [ 16 , 17 , 18 ], organizational refinement [ 19 ] and convection [ 20 ]. The effect of SSMF on the microstructure during solidification is bound to the properties of the material after solidification, such as mechanical properties [ 21 ], thermoelectric properties [ 21 , 22 ] and magnetic properties [ 23 , 24 ].…”

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Strong magnetic field effect on the nucleation of a highly undercooled Co-Sn melt

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