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Uses of ferromagnetic materials may be sorted according to: |
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Soft magnets; e.g. Fe - alloys |
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- Everything profiting from an "iron core": Transformers, Motors, Inductances, ...
- Shielding magnetic fields.
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Hard magnets; e.g. metal oxides or "strange" compounds. |
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- Permanent magnets for loudspeakers, sensors, ...
- Data storage (Magnetic tape, Magnetic disc drives, ...
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Even so we have essentially only Fe, Ni and Co (+ Cr,
O and Mn in compounds) to work with, innumerable magnetic materials with optimized properties have been developed. |
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Strongest permanent magnets:
Sm2Co17
Nd2Fe14B |
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New complex materials (including "nano"materials) are needed and developed all the
time. | |
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Data storage provides a large impetus to magnetic material development and to employing
new effects like "GMR"; giant magneto resistance; a purely quantum mechanical effect. |
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© H. Föll (Electronic Materials - Script)
