氢化钙还原 Nd-Fe-B 烧结磁泥中的优质 Nd-Fe-B 粉末
水素化カルシウムは、Nd–Fe–B焼結磁石スラッジから高品質のNd–Fe–B粉末を還元しました
칼슘 수소화물은 Nd-Fe-B 소결 자석 슬러지에서 고품질 Nd-Fe-B 분말을 감소시켰습니다
Polvo de Nd-Fe-B de alta calidad reducido con hidruro de calcio procedente de lodos magnéticos sinterizados de Nd-Fe-B
Poudre de Nd-Fe-B de haute qualité réduite à l'hydrure de calcium à partir de boues magnétiques frittées Nd-Fe-B
Восстановленный гидридом кальция высококачественный порошок Nd – Fe – B из спеченного магнитного шлама Nd – Fe – B
Haibo Xu 徐海波 ¹, Qingmei Lu 路清梅 ¹ ², Liying Cong ¹, Haowen Tian ¹, Weiqiang Liu 刘卫强 ¹ ², Youhao Liu 刘友好 ² ³, Yunqiao Wang ⁴, Jingwu Chen 陈静武 ² ³, Xiaofei Yi 衣晓飞 ² ³, Ming Yue 岳明 ¹ ²
¹ Key Lab of Advanced Functional Materials, Ministry of Education, Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100124, China
中国 北京 北京工业大学 材料科学与工程学院 新型功能材料教育部重点实验室
² State Key Laboratory of Rare Earth Permanent Magnetic Materials, Hefei 231500, China
中国 合肥 稀土永磁材料国家重点实验室
³ Earth–Panda Advanced Magnetic Materials Co., Ltd., Hefei 231500, China
中国 合肥 安徽大地熊新材料股份有限公司
⁴ Beijing Zhong Ke San Huan Research, Beijing 102200, China
中国 北京 中科三环研究院
The structural and magnetic properties were studied for recycling Nd–Fe–B powders from Nd–Fe–B sintered magnets sludge via reduction diffusion (RD) with calcium hydride (CaH2) particles. For comparison, traditional reducing agent calcium granules were applied to prepare recycled Nd–Fe–B powders. Finer particle size and better size distribution as well as lower impurity content are achieved by using CaH2 instead of Ca. In detail, the average particle size of the recycled Nd–Fe–B powder is reduced from 4.66 to 3.43 μm, and the bimodal distribution disappears. Moreover, the residual calcium content and oxygen content are reduced to about 0.080 wt% and 0.32 wt%.
As a consequence, the room-temperature magnetization of the CaH2-recycled Nd–Fe–B powder is increased to 146.30 emu/g, 6.8% and 33%, respectively, higher than that of Ca-reduced powder and the initial sludge. Further analysis indicates that CaH2 is able to reduce the sludge at lower temperature to fabricate well-dispersed, uniform recycled powder with high magnetization arising from a combination factors of its low melting point, low thermodynamic behavior, and the release of hydrogen during the reaction.
