Crystal growth of rare earth–iron intermetallic compounds by the flux-creep-up method

Abstract

A new flux method for the crystal growth of rare earth–iron intermetallic compounds was developed. In this method, the rare-earth flux creeps up the inner surface of a BN-coated crucible during the cooling process, and free-standing crystals are left on the bottom of the crucible. This method was applied to the crystal growth of compounds in Sm–Fe and Nd–Fe systems, and crystals of SmFe 2, SmFe 3, Sm 6Fe 23, and Nd 6Fe 13− x Al 1+ x were grown for the first time. In particular, SmFe 7 is a new phase in the Sm–Fe system with high performance as a permanent magnet. Since the chemical composition of the mixture in the crucible changes in accordance with the creep-up of the flux, this method may be promising in the search for new phases as well as for the crystal growth of known materials.