Modeling of permanent magnets: Interpretation of parameters obtained from the Jiles{endash}Atherton hysteresis model

Journal Article · Mon Apr 01 04:00:00 EST 1996 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.361975· OSTI ID:280095

Lewis, L H ^[1]; Gao, J; Jiles, D C ^[2]; Welch, D O ^[1]

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1. Department of Applied Science, Brookhaven National Laboratory, Upton, New York 11973 (United States)
2. Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)

The Jiles{endash}Atherton theory is based on considerations of the dependence of energy dissipation within a magnetic material resulting from changes in its magnetization. The algorithm based on the theory yields five computed model parameters, {ital M}{sub {ital S}}, {ital a}, {alpha}, {ital k}, and {ital c}, which represent the saturation magnetization, the effective domain density, the mean exchange coupling between the effective domains, the flexibility of domain walls and energy-dissipative features in the microstructure, respectively. Model parameters were calculated from the algorithm and linked with the physical attributes of a set of three related melt-quenched permanent magnets based on the Nd{sub 2}Fe{sub 14}B composition. Measured magnetic parameters were used as inputs into the model to reproduce the experimental hysteresis curves. The results show that two of the calculated parameters, the saturation magnetization {ital M}{sub {ital S}} and the effective coercivity {ital k}, agree well with their directly determined analogs. The calculated {ital a} and {alpha} parameters provide support for the concept of increased intergranular exchange coupling upon die upsetting, and decreased intergranular exchange coupling with the addition of gallium. {copyright} {ital 1996 American Institute of Physics.}

• Research Organization: Brookhaven National Laboratory
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 280095
• Report Number(s): CONF-951101--
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 79; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
COBALT BORIDES
COERCIVE FORCE
DOMAIN STRUCTURE
ENERGY LOSSES
EXCHANGE INTERACTIONS
GALLIUM ADDITIONS
HOT PRESSING
HYSTERESIS
IRON BORIDES
MAGNETIC MATERIALS
MAGNETIZATION
MATHEMATICAL MODELS
MICROSTRUCTURE
NEODYMIUM BORIDES
PERMANENT MAGNETS
THERMOMECHANICAL TREATMENTS