Degaussing

Stan Zurek, Degaussing, Encyclopedia Magnetica,
http://www.e-magnetica.pl/doku.php/degaussing

Degaussing - a process of demagnetisation in which the remaining net magnetisation is partially or completely removed from the the given material, component, or device. ¹⁾

The name “degaussing” is related to the CGS system in which the magnetic flux density is measured in the units of gauss.

See also the main article: Process of demagnetisation.

Degaussing (demagnetisation) by applying AC excitation and slowly reducing the amplitude. In the example as shown the degaussing is incomplete because there is still some remaining net magnetisation (position of the dot in the graph of the hysteresis loop). The reason for incomplete degaussing could be too low initial amplitude or too quick decrease of the AC excitation.²⁾