Magnetic Materials
MAGETIC MATERIALS
On the basis of magnetic properties like susceptibility and permeability, magnetic materials are categorized in following groups:
• Diamagnetic substance: The magnetic substance in which an atom or ion contains paired electrons. The total magnetic moment is practically zero as a result of nullifying effect of the orbital and spin angular moments. It shows magnetic moment anti-parallel to the field. Such substances possess following properties:
(i) Value of susceptibility, susceptibility is negative and small.
(ii) Relative permeability, μr <1.
(iii) susceptibility is independent of temperature.
Examples: Gold, copper, Silver, Diamond, Water, H2 and N2 etc.
• Paramagnetic substance: The magnetic substance in which atom or ion has one or more unpaired electrons and thus possesses permanent magnetic moment. Such substances possess following properties:
(i) Value of susceptibility is positive but very small.
(ii) Relative permeability μr >1.
(iii) susceptibility is dependent of temperature.
(iv) It follows Curie law (= C/T)
Examples: Tungsten, Al, Mn & O2 etc.
• Ferromagnetic substance: The magnetic substance in which a strong interaction between adjacent magnetic moments tends to align them parallel to one another is called ferromagnetic. Such substances possess following properties:
(i) Value of susceptibility is positive and very large.
(ii) Relative permeability μr >>1.
(iii) susceptibility is dependent of temperature.
(iv) It follows Curie law
Examples: Fe, Co & Ni etc.
Also see (Click on these quick links) :
1. Domain Theory of Ferromagnetism: http://www.askmattrab.com/notes/93-domain-theory-of-ferromagnetism
2. Antiferromagnetic and Ferrimagnet: http://www.askmattrab.com/notes/94-antiferromagnet-and-ferrimagnet
3. Magnetic Materials: http://www.askmattrab.com/notes/95-magnetic-materials
4. Working of the Transformer: http://www.askmattrab.com/notes/97-working-of-the-transformer