Synthesis of Anisotropic Magnetic Powders Composed of Nanocomposite Hard and Soft magnetic Phases

Abstract

A nanocomposite permanent magnet, which is a nano-scale mixture of a hard magnetic phase and a soft magnetic phase, has become more and more attractive as a new magnetic material. Exchange coupling between the soft magnetic phase and the hard magnetic phase causes the magnetization vector of the soft phase to be aligned with that of the hard phase, resulting in high magnetization due to the soft phase and high coercivity due to the hard phase. Recently, mechanical alloying (MA) and the melt-spinning method have been applied to the production of nanocomposite magnets. These composite magnets, however, are magnetically isotropic, and a magnetically anisotropic composite magnet is significantly required. Therefore, in this experiment, we have tried to synthesize anisotropic nanocomposite magnetic powders by vacuum deposit method, and the corrosion behavior of them also investigated.