Abstract Spin reorientation temperature ( T S R ) of sintered Nd2Fe14B ingots, hydrogenation-disproportionation-desorption-recombination (HDDR) processed Nd2Fe14B powder and surfactant-assisted ball-milled ultrafine nanostructured Nd2Fe14B particles has been determined. T S R value was found to decrease from 135 K for sintered Nd2Fe14B ingot to 129 K for HDDR processed Nd2Fe14B particles of 50-200 μm size composed of ∼300 nm grains. Interestingly, T S R value was increased after surfactant-assisted (SA) ball milling of HDDR powder reaching 134 K for 1-2 μm particles and 136 K for ∼300 nm isolated single-crystalline particles. Transformation of single-crystalline particles to polycrystalline flakes after intense SA-ball milling resulted in a decrease of the T S R to a value of 128 K. A detailed crystallographic, microstructural, and magnetic investigations have been performed and the possible reasons for the variation of T S R value have been discussed.

中文翻译：

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通过表面活性剂辅助球磨获得的超细纳米结构 Nd2Fe14B 颗粒的自旋重定向温度

摘要 已确定烧结 Nd2Fe14B 锭、氢化-歧化-解吸-复合 (HDDR) 处理的 Nd2Fe14B 粉末和表面活性剂辅助的球磨超细纳米结构 Nd2Fe14B 颗粒的自旋重定向温度 (TSR)。发现 TSR 值从烧结 Nd2Fe14B 锭的 135 K 降低到 HDDR 加工的 Nd2Fe14B 颗粒的 129 K，其尺寸为 50-200 μm，由~300 nm 晶粒组成。有趣的是，表面活性剂辅助 (SA) 球磨 HDDR 粉末后，1-2 μm 颗粒达到 134 K，约 300 nm 分离的单晶颗粒达到 136 K，TSR 值增加。在强烈的 SA 球磨后，单晶颗粒转变为多晶薄片导致 TSR 值降低至 128 K。详细的晶体学、微观结构、