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Title: Modeling of micromagnetic Barkhausen activity using a stochastic process extension to the theory of hysteresis

Abstract

Recent work by Bertotti [IEEE Trans. Magn. [bold MAG]-[bold 24], 621 (1988)] and others has shown that it is possible to model the micromagnetic Barkhausen discontinuities at the coercive point using a two-parameter stochastic model. However, the present formulation of the model is restricted to limited regions of the hysteresis curve over which [ital dM]/[ital dH] is approximately constant and when [ital dH]/[ital dt] is held at a constant rate. A natural extension of this model is to take the basic result, in which the level of Barkhausen activity in one time period is related to the activity in the previous time period, and increment it by a small amount which is dependent on the differential permeability. The extension of the model proposed here uses the theory of ferromagnetic hysteresis to determine the differential permeability at any point of the hysteresis loop. The Barkhausen activity is then assumed to vary in proportion to the differential permeability. The resulting model allows the Barkhausen sum of discontinuous changes in magnetization to be modelled around the entire hysteresis loop, leading to an important generalization of the basic model.

Authors:
 [1];  [2];  [3]
  1. (Ames Laboratory, Center for Nondestructive Evaluation, Department of Materials Science and Engineering and Department of Electrical Engineering, Iowa State University, Ames, Iowa 50011 (United States))
  2. (Ames Laboratory, Center for Nondestructive Evaluation, and Department of Physics, Iowa State University, Ames, Iowa 50011 (United States))
  3. (Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States))
Publication Date:
OSTI Identifier:
6609340
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; (United States); Journal Volume: 73:10
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; MAGNETIC MATERIALS; HYSTERESIS; MAGNETIC SUSCEPTIBILITY; MAGNETIZATION; MATHEMATICAL MODELS; STOCHASTIC PROCESSES; MAGNETIC PROPERTIES; MATERIALS; PHYSICAL PROPERTIES 665000* -- Physics of Condensed Matter-- (1992-)

Citation Formats

Jiles, D.C., Sipahi, L.B., and Williams, G. Modeling of micromagnetic Barkhausen activity using a stochastic process extension to the theory of hysteresis. United States: N. p., 1993. Web. doi:10.1063/1.353541.
Jiles, D.C., Sipahi, L.B., & Williams, G. Modeling of micromagnetic Barkhausen activity using a stochastic process extension to the theory of hysteresis. United States. doi:10.1063/1.353541.
Jiles, D.C., Sipahi, L.B., and Williams, G. 1993. "Modeling of micromagnetic Barkhausen activity using a stochastic process extension to the theory of hysteresis". United States. doi:10.1063/1.353541.
@article{osti_6609340,
title = {Modeling of micromagnetic Barkhausen activity using a stochastic process extension to the theory of hysteresis},
author = {Jiles, D.C. and Sipahi, L.B. and Williams, G.},
abstractNote = {Recent work by Bertotti [IEEE Trans. Magn. [bold MAG]-[bold 24], 621 (1988)] and others has shown that it is possible to model the micromagnetic Barkhausen discontinuities at the coercive point using a two-parameter stochastic model. However, the present formulation of the model is restricted to limited regions of the hysteresis curve over which [ital dM]/[ital dH] is approximately constant and when [ital dH]/[ital dt] is held at a constant rate. A natural extension of this model is to take the basic result, in which the level of Barkhausen activity in one time period is related to the activity in the previous time period, and increment it by a small amount which is dependent on the differential permeability. The extension of the model proposed here uses the theory of ferromagnetic hysteresis to determine the differential permeability at any point of the hysteresis loop. The Barkhausen activity is then assumed to vary in proportion to the differential permeability. The resulting model allows the Barkhausen sum of discontinuous changes in magnetization to be modelled around the entire hysteresis loop, leading to an important generalization of the basic model.},
doi = {10.1063/1.353541},
journal = {Journal of Applied Physics; (United States)},
number = ,
volume = 73:10,
place = {United States},
year = 1993,
month = 5
}
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