The Noise Generated in a Coil with a Ferromagnetic Core

It is well known that Barkhausen noise will be induced in a coil which has a ferromagnetic core, if the core is subjected to any considerable degree of varying or alternating magnetization due to current flowing in the coil or due to a magnetizing field from some external source. This effect is ascribed to irreversible magnetization processes, such as irreversible domain wall movements, and has been investigated in considerable detail. It has recently been utilized to estimate the amount of the contribution of such irreversible processes to the total magnetization (Tebble, Skidmore, and Corner 1950).