Chapter 8.2

Created by jtrance 

Upgrade to
remove ads

7 terms · Magnetic Material Classifications

Diamagnetism

Has a NEGATIVE and SMALL magnetic susceptibility. When a diamagnetic material is placed in a magnetic field, the magnetization vector M is opposite the direction to the applied field μoH... the resulting B field is less than μoH.

Atoms have closed subshells.

ex. organic materials, many polymers; covalent solids Si, Ge... Cu, Ag, Au.

note: they are superconductors below critical temperature.

Paramagnetism

Has a POSITIVE and SMALL magnetic susceptibility. Molecules and atoms have random dipole moments in absence of a field.

ex. Alkali and transition metals

Ferromagnetism

Has LARGE, PERMANENT magnetizations even without an applied magnetic field. Magnetic susceptibility is positive and very large (even infinite). Origin is explained by exchange interaction

ex. Some transition and rare earth metals:
Fe, Co, Ni, Gd, Dy

note: occurs BELOW Curie temperature Tc. Above Tc, it is paramagnetic.

Antiferromagnetism

Has a SMALL but POSITIVE susceptibility. Has no magnetization without and applied field (and is therefore ANTI-ferromagnetic).

ex. mainly salts and oxides of transition metals... MnO, NiO, MnF2, Cr, Mn

note: occurs BELOW the Neel temperature, T_N. Above T_N, it is paramagnetic

Ferrimagnetism

Has similar behavior to ferromagnets BELOW the Curie temperature Tc. Above Tc, they are paramagnetic. The material can possess magnetization even in absence of an applied field. Typically non conducting... used in a lot of high frequency electronics.

Classification of magnetic materials [table 8.2

What are the two most used magnetic materials in EE again?

Ferromagnets and Ferrimagnets.

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set