ABSTRACT

Post-neodymium magnets that possess high heat resistance, coercivity, and (BH)_max are desired for future-generation motors. However, the candidate materials for post-neodymium magnets such as Sm₂Fe₁₇N₃ and metastable magnetic alloys have certain process-related problems: low sinterability due to thermal decomposition at elevated temperatures, deterioration of coercivity during sintering, and the poor coercivity of the raw powder. Various developments in powder processing are underway with the aim of overcoming these problems. So far, the development of advanced powder metallurgy techniques has achieved Sm₂Fe₁₇N₃ anisotropic sintered magnets without coercivity deterioration, and advances in chemical powder synthesis techniques have been successful in producing Sm₂Fe₁₇N₃ fine powders with huge coercivity. The challenge of a new powder process is expected to open the way to realizing post-neodymium magnets.

摘要

下一代电动机需要具有高耐热性，矫顽力和（BH）_max的钕后磁铁。但是，用于钕后磁体的候选材料（例如Sm ₂ Fe ₁₇ N ₃和亚稳磁性合金）具有某些与工艺相关的问题：由于高温下的热分解而导致的可烧结性低，烧结过程中的矫顽力变差以及矫顽力差。生粉。为了克服这些问题，粉末加工的各种发展正在进行中。迄今为止，先进粉末冶金技术的发展已实现Sm ₂ Fe ₁₇ N ₃矫顽力不会降低的各向异性烧结磁体，化学粉末合成技术的进步已成功地生产出具有大矫顽力的Sm ₂ Fe ₁₇ N ₃细粉。新型粉末工艺的挑战有望为实现钕后磁铁开辟道路。