Magnetization and magnetostriction processes in Tb(0.27−0.30)Dy(0.73−0.70)Fe(1.9−2.0)

Abstract

The present analysis provides Tb(0.27−0.30)Dy(0.73−0.70)Fe(1.9−2.0) magnetization and magnetostriction states during applied magnetic field and stress processes by minimizing the total magnetic free energy in the presence of a parameter selected inverse exponential magnetic free energy distribution. A comparison between experimental and model results shows that the model provides a qualitatively accurate description of the magnetostriction and magnetization in Tb(0.27−0.30)Dy(0.73−0.70)Fe(1.9−2.0) during applied magnetic field processes for a range of constant uniaxial applied stresses. Therefore, the model appears to be a useful tool for the analysis of Tb(0.27−0.30)Dy(0.73−0.70)Fe(1.9−2.0) applications with constant stress or strain dependent stress states. Furthermore, the good qualitative agreement between model and experiment supports the contention that the magnetostriction and magnetization response of Tb(0.27−0.30)Dy(0.73−0.70)Fe(1.9−2.0) is influenced by a defect induced defocusing of local magnetization direction about the average magnetization direction.

Effect of Stress on Switched Reluctance Motors: A Magneto-Elastic Finite-Element Approach Based on Multiscale Constitutive Laws

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A homogenized energy framework for ferromagnetic hysteresis

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