Theoretical analysis of the magnetic field and eddy current within a rectangular giant magnetostrictive material plate

Abstract

In this paper, we present the distribution functions of magnetic field intensity and eddy current intensity within a rectangular magnetostrictive material plate. Firstly, on the basis of Maxwell's theory, the mathematical model for the magnetic field within the plate is established. Then, the governing equation for determining the magnetic field is solved by Fourier transform; an error in Stoll's book (1983) is corrected. Furthermore, the function of eddy current intensity is deduced. Next, the expressions of the magnetic field and eddy current are given in the case of the external magnetic field and the plate makes an angle of θ. Lastly, taking rectangular giant magnetostrictive plate is parallel to external magnetic field as example, the influencing factors of the inner magnetic field and eddy current are unveiled: the skin effect is enhanced with the increase of the exciting frequency, the relative permeability or conductivity; the higher the relative permeability or conductivity, the more significant the eddy current density increases.