Application of magnetic levitation to materials processing }

I. Mogi^1,2 - M. Hamai¹ - T. Sato¹ - K. Takahashi^1,2 - S. Awaji^1,2 - K. Watanabe^1,2 - M. Motokawa²

¹ Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
² CREST, Japan Science and Technology Corporation, Japan

Abstract
Magnetic levitation of diamagnetic materials under gradient strong magnetic fields was applied to solution crystal growth and melting of levitating materials, and the behavior of levitating materials was investigated. In the crystal growth of NH₄Cl in a levitating droplet, heterogeneous nucleation was considerably suppressed, and dendrites grew along the droplet surface. In the solution crystal growth in a container, the NH₄Cl crystal was levitated in the solution without contact with the walls and the solution surface. Containerless melting and solidification of paraffin was performed with the magnetic levitation furnace, and the Marangoni convection was observed in the melt droplet. Furthermore, levitating alignment of bismuth particles and levitating orientation of a paraffin rod are described. Tables 2, Figs 5, Refs 8.