Abstract

X-ray diffraction and differential thermal analyses are used to study multicomponent Nd–R–Fe–B (R = Pr, Ce, La) alloys prepared by induction melting in an inert gas atmosphere and subsequent forced cooling upon casting in a massive cast iron mold. The effect of substitution of light rare-earth metals for neodymium on the phase composition and morphology of the cast alloys with 0–6.9 wt % Pr, 0–10.0 wt % Ce, and 0–9.0 wt % La, which are used as precursors in manufacturing sintered permanent magnets with high hysteretic characteristics, is studied. The main structural constituents of the alloys are shown to be a magnetic phase with the Nd₂Fe₁₄B-type structure and Nd-rich, R_1.1Fe₄B₄, and R₂Fe₁₇ phases. The phase transformation temperatures of the alloys are determined, which allow us to correct the sintering temperatures of permanent magnet powder blanks prepared from the cerium- and lanthanum-containing alloys.

中文翻译：

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烧结永磁体用铸造 Nd–R–Fe–B (R = Pr, Ce, La) 合金的组织

摘要

X 射线衍射和差热分析用于研究多组分 Nd-R-Fe-B (R = Pr、Ce、La) 合金，这些合金是通过在惰性气体气氛中感应熔炼并随后在大块铸铁中铸造时强制冷却而制备的模具。轻稀土金属替代钕对用作前驱体的 0-6.9 wt % Pr、0-10.0 wt % Ce 和 0-9.0 wt % La 铸造合金的相组成和形貌的影响在制造具有高磁滞特性的烧结永磁体方面进行了研究。合金的主要结构成分显示为具有 Nd ₂ Fe ₁₄ B 型结构和富 Nd、R _1.1 Fe ₄ B ₄和 R _{2的磁性相}Fe ₁₇相。确定了合金的相变温度，这使我们能够校正由含铈和镧合金制备的永磁粉末坯料的烧结温度。