Computational modeling of magnetic hysteresis with thermal effects

0474872 - ÚTIA 2019 RIV NL eng J - Journal Article
Kružík, Martin - Valdman, Jan
Computational modeling of magnetic hysteresis with thermal effects.
Mathematics and Computers in Simulation. Roč. 145, č. 1 (2018), s. 90-105. ISSN 0378-4754. E-ISSN 1872-7166
R&D Projects: GA ČR GA13-18652S; GA ČR(CZ) GF16-34894L; GA ČR GA17-04301S; GA MŠMT(CZ) 7AMB16AT015
Institutional support: RVO:67985556
Keywords : Dissipative processes * hysteresis * micromagnetics
OECD category: Pure mathematics
Impact factor: 1.409, year: 2018
http://library.utia.cas.cz/separaty/2017/MTR/kruzik-0474872.pdf

We study computational behavior of a mesoscopic model describing temperature/external magnetic field-driven evolution of magnetization. Due to nonconvex anisotropy energy describing magnetic properties of a body, magnetization can develop fast spatial oscillations creating complicated microstructures. These microstructures are encoded in Young measures, their first moments then identify macroscopic magnetization. Our model assumes that changes of magnetization can contribute to dissipation and, consequently, to variations of the body temperature a ecting the length of magnetization vectors. In the ferromagnetic state, minima of
the anisotropic energy density depend on temperature and they tend to zero as we approach the so-called Curie temperature. This brings the specimen to a paramagnetic state. Such a thermo-magnetic model is fully discretized and tested on two-dimensional examples. Computational results qualitatively agree with experimental observations. The ownMATLAB code used in our simulations is available for download.
Permanent Link: http://hdl.handle.net/11104/0272093