Enhanced magnetic properties and improved corrosion performance of nanocrystalline Pr-Nd-Y-Fe-B spark plasma sintered magnets

• 作者: Qingzheng Jiang Jie song Qingfang Huang Sajjad Ur Rehman Lunke He Qingwen Zeng Zhenchen Zhong
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2020,（23）
• 页码范围: 138-144
• 页数: 7页
• 语种: 英文

摘要

Recently it is a hot topic to make full use of high abundant Y element in Nd2Fe14B-type permanent mag-nets.In contrast to Pr and Nd elements,Y shows different metallurgical behaviors during preparation process.In this paper,we have explored the magnetic properties,microstructures and corrosion perfor-mance of Pr-Nd-Y-Fe-B magnets fabricated by spark plasma sintering (SPS) technique from the ribbons of nanocrystalline and amorphous precursors,respectively.The coercivity and maximum energy prod-uct were improved for the magnets prepared from amorphous precursor materials (denoted as SPS-A hereafter) compared with the magnets prepared from crystalline precursor materials (denoted as SPS-C hereafter).Magnetic properties of Jr =0.79 T,Hci =864 kA/m,and (BH)max =102 kJ/m3 were obtained for SPS-A magnets.In contrast with SPS-C magnets,the magnetic properties of SPS-A magnets are not so sensitive to the preparation conditions,which is quite beneficial to the homogeneity of microstruc-ture and enhancement of coercivity for large-scale production of the designated magnets.Aggregated(Pr,Nd,Y)-rich phase was found out in SPS-C magnets.Pr and Nd elements are rich at grain boundary while Y is distributed uniformly at main phase and grain boundary phase.The strip grains and equiaxed grains exist in SPS-C and SPS-A magnets,respectively.The enhanced magnetic properties for SPS-A mag-nets are accredited to the uniform distribution of rare-earth-rich phase and low demagnetization factor.It is revealed by electrochemical test and dipping test that the corrosion potential is more positive and the corrosion rate is slower for the SPS-A magnets in 3.5 wt.％ NaCl solution.The work is also expected to shed light on developing the nanocrystalline Pr-Nd-Y-Fe-B SPSed high-performance magnets in industry.