Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles
With increasing demand for magnets in energy conversion systems, the quest for the development and understanding of novel processing routes to produce permanent magnets has become urgent. We report a novel mechanochemical process for the synthesis of Nd2(Fe,Co)14B magnetic particles with a high coer...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2020
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| Online Access: | https://hdl.handle.net/10356/141075 |
| _version_ | 1811691622225674240 |
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| author | Zhong, Yaoying Chaudhary, Varun Tan, Xipeng Parmar, Harshida Ramanujan, Raju Virajaya |
| author2 | School of Materials Science and Engineering |
| author_facet | School of Materials Science and Engineering Zhong, Yaoying Chaudhary, Varun Tan, Xipeng Parmar, Harshida Ramanujan, Raju Virajaya |
| author_sort | Zhong, Yaoying |
| collection | NTU |
| description | With increasing demand for magnets in energy conversion systems, the quest for the development and understanding of novel processing routes to produce permanent magnets has become urgent. We report a novel mechanochemical process for the synthesis of Nd2(Fe,Co)14B magnetic particles with a high coercivity of 12.4 kOe. This process involves the reduction of neodymium oxide, iron oxide, cobalt oxide and boron anhydride in the presence of a calcium reducing agent and a CaO diluent. The formation mechanism of Nd2(Fe,Co)14B changed with increasing CaO content, and the average crystal size of the Nd2(Fe,Co)14B particles also increased, resulting in an increase in the coercivity values. The reaction mechanism during milling was revealed through a study of the phase transformations as a function of milling time. It was found that unlike self-propagating reactions, this reduction reaction during milling requires continuous input of mechanical energy to reach a steady state. |
| first_indexed | 2024-10-01T06:22:49Z |
| format | Journal Article |
| id | ntu-10356/141075 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T06:22:49Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1410752020-06-04T01:07:03Z Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles Zhong, Yaoying Chaudhary, Varun Tan, Xipeng Parmar, Harshida Ramanujan, Raju Virajaya School of Materials Science and Engineering Rolls-Royce@NTU Corporate Lab Engineering::Materials Mechanochemical Nd2(Fe,Co)14B With increasing demand for magnets in energy conversion systems, the quest for the development and understanding of novel processing routes to produce permanent magnets has become urgent. We report a novel mechanochemical process for the synthesis of Nd2(Fe,Co)14B magnetic particles with a high coercivity of 12.4 kOe. This process involves the reduction of neodymium oxide, iron oxide, cobalt oxide and boron anhydride in the presence of a calcium reducing agent and a CaO diluent. The formation mechanism of Nd2(Fe,Co)14B changed with increasing CaO content, and the average crystal size of the Nd2(Fe,Co)14B particles also increased, resulting in an increase in the coercivity values. The reaction mechanism during milling was revealed through a study of the phase transformations as a function of milling time. It was found that unlike self-propagating reactions, this reduction reaction during milling requires continuous input of mechanical energy to reach a steady state. NRF (Natl Research Foundation, S’pore) 2020-06-04T01:07:03Z 2020-06-04T01:07:03Z 2017 Journal Article Zhong, Y., Chaudhary, V., Tan, X., Parmar, H., & Ramanujan, R. V. (2017). Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles. Nanoscale, 9(47), 18651-18660. doi:10.1039/c7nr04703g 2040-3364 https://hdl.handle.net/10356/141075 10.1039/c7nr04703g 28905064 2-s2.0-85038397411 47 9 18651 18660 en Nanoscale © 2017 The Royal Society of Chemistry. All rights reserved. |
| spellingShingle | Engineering::Materials Mechanochemical Nd2(Fe,Co)14B Zhong, Yaoying Chaudhary, Varun Tan, Xipeng Parmar, Harshida Ramanujan, Raju Virajaya Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title | Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title_full | Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title_fullStr | Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title_full_unstemmed | Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title_short | Mechanochemical synthesis of high coercivity Nd2(Fe,Co)14B magnetic particles |
| title_sort | mechanochemical synthesis of high coercivity nd2 fe co 14b magnetic particles |
| topic | Engineering::Materials Mechanochemical Nd2(Fe,Co)14B |
| url | https://hdl.handle.net/10356/141075 |
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