Ga添加钕铁硼磁体的原位加热透射电镜研究
黎国猛,彭众杰,相春杰,丁开鸿,徐先东*
(1.湖南大学材料科学与工程学院,湖南长沙410082;2.烟台东星磁性材料股份有限公司,山东烟台265500)
摘 要 对Ga添加钕铁硼磁体中RE6Fe13Ga相的形成过程目前仍缺乏清晰的认知。本文针对这一问题对Ga添加钕铁硼磁体进行了原位加热透射电镜研究,结果表明:含Ga非晶相在原位加热过程中能扩散至周围的晶间相区域并溶解其中部分面心立方(fcc)结构富稀土相,在RE6Fe13Ga相的形成过程中起主要作用;fcc结构富稀土相在加热过程中会逐渐被氧化并向Mn2O3结构(空间群Ia3)转变,且当晶间相区域中基本只有fcc结构富稀土相时,加热过程中仅发生这种氧化引起的相结构转变。本工作为理解RE6Fe13Ga相的形成过程提供了重要的实验依据。
关键词 钕铁硼;原位透射电镜;原位加热;相转变
中图分类号:TG132.2 72;O766.1;TG115.21+5.3 文献标识码:A
In-situheating transmission electron microscopy study of a Ga-doped Nd-Fe-B magnet
LI Guomeng1, PENG Zhongjie2, XIANG Chunjie2, DING Kaihong2, XU Xiandong1*
(1. College of Materials Science and Engineering, Hunan University, Changsha Hunan 410082; 2. Yantai Dongxing Magnetic Materials Inc, Yantai Shandong 265500)
Abstract The formation process of the RE6Fe13Ga phase in Ga-doped Nd-Fe-B magnets is not well understood. To investigate this, we conducted in-situ heating transmission electron microscopy (TEM) studies on a Ga-doped Nd-Fe-B magnet. The results indicated that the Ga-containing amorphous phase can diffuse into the surrounding intergranular regions and partially dissolve thefcc RE (rare earth)-rich phases during in-situ heating. This highlighted the significant role of the Ga-containing amorphous phase in the formation process of the RE6Fe13Ga phase. Thefcc RE-rich phase was gradually oxidized during heating and transformed into the Mn2O3 structure (space group Ia3). When thefcc RE-rich phase became the dominant intergranular phase, only oxidation-induced structural transformation occurred during heating. This work provides important experimental evidence for understanding the formation process of the RE6Fe13Ga phase.
Keywords Nd-Fe-B; in-situ TEM; in-situ heating; phase transformation
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