An Electromagnetic Compounding Technique for Counteracting the Thermoelectric Magnetic Effect During Directional Solidification Under a Transverse Static Magnetic Field

作者：Shen, Zhe; Zhou, Bangfei; Zhong, Yunbo^*; Dong, Licheng; Wang, Huai; Fan, Lijun; Zheng, Tianxiang; Li, Chuanjun; Ren, Weili; Xuan, Weidong; Ren, Zhongming

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2018, 49A(8): 3373-3382.

DOI：10.1007/s11661-018-4732-y

• THERMOSOLUTAL CONVECTION
• TRANSPORT PHENOMENA
• FRECKLE FORMATION
• ALLOYS
• MACROSEGREGATION
• MODEL
• MICROSTRUCTURE
• MICROGRAVITY

An external direct current (DC) was introduced to counteract the thermoelectric magnetic effect during the directional solidification of Sn-10 wt pct Bi alloy under a 0.5 T transverse static magnetic field. The results show that the single-side Bi segregation induced by the thermoelectric magnetic effect gradually becomes weakened, disappeared, and then reversed with the increasing current density of the external DC. Therefore, a new method for counteracting the thermoelectric magnetic effect during materials processing under the magnetic field was proposed. In order to verify this method, the absolute thermoelectric power of Sn-10 wt pct Bi alloy and the internal thermoelectric current under the experimental conditions were measured and calculated, respectively. A 2D numerical simulation was established to simulate the evolution of the solid-liquid interface morphology, flow field, and composition segregation with the increasing current density of the external DC during directional solidification under a transverse static magnetic field. The present study not only facilitates the understanding of the effects of the forced flows on the directionally solidified microstructures and composition segregation, but also provides a new way for eliminating segregation and obtaining the higher-quality solidification structure by using the electromagnetic compounding technique.

• 出版日期2018-8
• 单位上海大学