Formation of Structure and Magnetic Properties of NdFeB Powders Quenched by Centrifugal Sputtering

This paper describes the structure and magnetic properties of nanocrystalline NdFeB hard magnetic materials and their evolution during quenching of melted alloys by centrifugal sputtering followed by finishing annealing. The investigation covers a range of NdFeB alloys of typical composition of commercial grades. Results of the study of critical parameters defining the formation of rapid quenched particles of optimal sizes are described. As shown, the maximum magnetic properties can be obtained at completed crystallization process, which is featured by the maximum quantity of basic hard magnetic phase Nd2Fe14B and minimum quantity of soft magnetic alpha-iron.