Magnetic Barkhausen Noise and stress strain curve have been measured here.
(When the external magnetic field is changed, domains change size by the domain walls moving within the crystal lattice so local abrupt changes of the magnetization occur which are measured as electric signals, it’s called magnetic Barkhausen noise.)
The maximum value of magnetic saturation reached depends on the direction of the anisotropy of the hard boundary.
Coercivity (a material's ability to resist demagnetization in the presence of a magnetic field) depends both on the thickness of the hard boundary and the anisotropy constant (measure of how strongly a material's magnetic properties depend on direction).
(Magnetic anisotropy is defined as the dependency of magnetic properties on a preferred crystallographic direction. It is the required energy to deflect the magnetic moment in a single crystal from the easy to the hard direction of magnetization.
Exchange energy is a quantum-mechanical effect that determines the alignment of magnetic spins in a material.
Magnetostatic energy is energy required to create the magnetic poles of a body against the internal magnetic field.
Zeeman energy is the potential energy of a magnetized object in an external magnetic field.)
The anisotropy and magnetostatic energy gradually decreases as the applied field decreases from saturation. Zeeman energy increases slightly with the boundary thickness.
The effect of plastic strain( It refers to the permanent deformation of a material that occurs after the material has surpassed its elastic limit) depends on the angle of misalignment between the hard boundary and the soft grain, which affects the demagnetizing and anisotropy energy.
Source:
https://www.mdpi.com/2673-8724/5/1/1#
Definitions are from AI and wikipedia.
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