Abstract The correlation between preparation conditions and microstructure as well as magnetic properties were studied for Sm(Co0.665Fe0.25Cu0.06Zr0.025)7 magnets. Increase of sintering temperature from 1468 to 1493 K promotes the amalgamation of small grains into big ones, resulting in an enlargement of average grain size from 10 to 25 μm and diffusion of Cu from inner grains to Cu-lean grain boundaries. As a result, the demagnetization curve squareness of the magnets improves substantially, leading to a remarkable enhancement of the maximum energy product from 21.3 to 27.1 MGOe. The coercivity of the magnets drops from 25.3 to 16.0 kOe at the same time, which was verified by the increase of the average domain width from 1.1 μm in small grains to 2.5 μm in big grains. It is therefore concluded that tuning of the preparation conditions causes a more homogeneous distribution of Cu, which is crucial for the improvement of magnetic properties.

中文翻译：

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Cu在晶界的再分布对Sm(Co 0.665 Fe 0.25 Cu 0.06 Zr 0.025 ) 7 永磁体磁性能的影响

摘要 研究了Sm(Co0.665Fe0.25Cu0.06Zr0.025)7磁体的制备条件与显微组织及磁性能的相关性。将烧结温度从 1468 K 提高到 1493 K，促进了小晶粒向大晶粒的合并，导致平均晶粒尺寸从 10 μm 扩大到 25 μm，并且 Cu 从内部晶粒扩散到贫 Cu 晶界。结果，磁体的退磁曲线矩形度显着提高，导致最大能量积从21.3 MGOe显着提高到27.1 MGOe。同时，磁体的矫顽力从 25.3 kOe 下降到 16.0 kOe，这通过平均畴宽度从小晶粒的 1.1 μm 增加到大晶粒的 2.5 μm 得到证实。