کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1798678 1524828 2015 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Preparation of Nd-Fe-B sintered magnets from HDDR-processed powder
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Preparation of Nd-Fe-B sintered magnets from HDDR-processed powder
چکیده انگلیسی
The electric-current sintering technique was used to fully densify hydrogenation-disproportionation-desorption-recombination (HDDR)-processed Nd-Fe-B powder at temperatures below the grain growth temperature in order to produce high-coercive bulk magnets. However, the sintered magnets exhibited anomalous coercivity reduction that depended on sintered density. Reheating examination of the sintered magnets revealed that the reduced coercivity was increased in proportion to the heating temperature, resulting in complete recovery of coercivity. As a result, the combination of electric-current sintering and post-annealing produced sintered magnets with a coercivity of 15 kOe. Scanning and transmission electron microscopy revealed no evidence that associated the anomalous coercivity reduction and recovery with grain boundary morphology. On the other hand, various HDDR powders with different particle sizes were sintered, and finer powders yielded lower coercivity after sintering, implying that the anomalous coercivity reduction was associated with particle surface oxides of the raw powder.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetism and Magnetic Materials - Volume 393, 1 November 2015, Pages 461-466
نویسندگان
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