Processing of nanostructured nickel-based magnetic materials
A systematic investigation into the structure and properties of five commercially available nickel-based soft magnetic materials was carried out. The five systems are Fe23Ni77, Fei6Ni77Cu7, Fei6Ni77Cu5Cr2, Fei6Ni77Mo7 and Fei6Ni77Nb7. These alloy systems were processed by ball milling to obtain t...
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| Format: | Research Report |
| Published: |
2008
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| Online Access: | http://hdl.handle.net/10356/5031 |
| _version_ | 1824456069485690880 |
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| author | School of Materials Science and Engineering |
| author2 | School of Materials Science & Engineering |
| author_facet | School of Materials Science & Engineering School of Materials Science and Engineering |
| author_sort | School of Materials Science and Engineering |
| collection | NTU |
| description | A systematic investigation into the structure and properties of five commercially
available nickel-based soft magnetic materials was carried out. The five systems
are Fe23Ni77, Fei6Ni77Cu7, Fei6Ni77Cu5Cr2, Fei6Ni77Mo7 and Fei6Ni77Nb7. These
alloy systems were processed by ball milling to obtain the compound with grain
size of several tens of nanometers in length scale. Depending on the exact
chemical composition, some amorphous or semi-amorphous phases were
deposited at the inter-granular layers as evidenced from the TEM micrographs.
As the grain size decreases to several tens of nanometer in scale, results of the
ball milled powders showed that the all the five systems exhibited coercivities
that increased with grain size, contrary to the random anisotropy model. These
were attributed to the internal stress generated from the mechanical forces.
Stress-annealed magnets sintered from the alloyed powders showed strong
dependency of the anisotropy on grain size where the coercivity decreases with
grain size. The effect of alloying elements on the magnetic properties of these
nanostructured magnets suggest that it is less significant compared to the effect
on grain size. Although the coercivity varies with the alloying elements, the
critical factor on its behaviour is dominated by the grain / particle size. |
| first_indexed | 2025-02-19T03:48:14Z |
| format | Research Report |
| id | ntu-10356/5031 |
| institution | Nanyang Technological University |
| last_indexed | 2025-02-19T03:48:14Z |
| publishDate | 2008 |
| record_format | dspace |
| spelling | ntu-10356/50312023-07-08T06:40:10Z Processing of nanostructured nickel-based magnetic materials School of Materials Science and Engineering School of Materials Science & Engineering DRNTU::Engineering::Materials::Magnetic materials A systematic investigation into the structure and properties of five commercially available nickel-based soft magnetic materials was carried out. The five systems are Fe23Ni77, Fei6Ni77Cu7, Fei6Ni77Cu5Cr2, Fei6Ni77Mo7 and Fei6Ni77Nb7. These alloy systems were processed by ball milling to obtain the compound with grain size of several tens of nanometers in length scale. Depending on the exact chemical composition, some amorphous or semi-amorphous phases were deposited at the inter-granular layers as evidenced from the TEM micrographs. As the grain size decreases to several tens of nanometer in scale, results of the ball milled powders showed that the all the five systems exhibited coercivities that increased with grain size, contrary to the random anisotropy model. These were attributed to the internal stress generated from the mechanical forces. Stress-annealed magnets sintered from the alloyed powders showed strong dependency of the anisotropy on grain size where the coercivity decreases with grain size. The effect of alloying elements on the magnetic properties of these nanostructured magnets suggest that it is less significant compared to the effect on grain size. Although the coercivity varies with the alloying elements, the critical factor on its behaviour is dominated by the grain / particle size. 2008-09-17T10:04:56Z 2008-09-17T10:04:56Z 2006 2006 Research Report http://hdl.handle.net/10356/5031 Nanyang Technological University 75 p. application/pdf |
| spellingShingle | DRNTU::Engineering::Materials::Magnetic materials School of Materials Science and Engineering Processing of nanostructured nickel-based magnetic materials |
| title | Processing of nanostructured nickel-based magnetic materials |
| title_full | Processing of nanostructured nickel-based magnetic materials |
| title_fullStr | Processing of nanostructured nickel-based magnetic materials |
| title_full_unstemmed | Processing of nanostructured nickel-based magnetic materials |
| title_short | Processing of nanostructured nickel-based magnetic materials |
| title_sort | processing of nanostructured nickel based magnetic materials |
| topic | DRNTU::Engineering::Materials::Magnetic materials |
| url | http://hdl.handle.net/10356/5031 |
| work_keys_str_mv | AT schoolofmaterialsscienceandengineering processingofnanostructurednickelbasedmagneticmaterials |