Soheil Talebian - Assistance Professor of Mechanical Engineering, Razi University, Kermanshah, Iran

In the present paper, excess eddy currents loss of Terfenol–D is studied and effects of magnetic field frequency, peak of magnetic flux density and diameter of Terfenol-D are investigated. To provide reliable data for the purpose of the paper, an experimental laboratory is fabricated and used to obtain major and minor hysteresis loops of Terfenol-D at different frequencies. In theoretical study, an eddy currents model based on non-uniform distribution of magnetic flux and nonlinear diffusion of electromagnetic fields is presented. Obtained results show that the values of excess losses are generally larger than classical losses and applying just classical model leads to wrong calculation of actual value of eddy currents losses. For the results obtained from the model, empirical model with respect to the magnetic field frequency and the peak value of magnetic flux density is achieved which can predict the excess eddy currents losses precisely. The model is validated at new conditions and the results point towards possibility to use the obtained empirical relations at the frequencies below ۲۰۰ Hz and different values of magnetic flux density.

excess eddy currents loss, Terfenol-D, nonlinear diffusion of magnetic field