Abstract
To characterize magnetic materials it is very important to take into account the initial magnetization curve and the magnetic hysteresis loop. Several approaches have been used to model these characteristics. However, some problems related to the accuracy of the results, especially at the knee of the curves have been encountered. This paper presents a contribution to solve this problem using both a simulated annealing algorithm to optimize the parameters of the Jiles-Atherton magnetic hysteresis model and the Brillouin theory to express the anhysteritic magnetization. The obtained results are in good agreement with measurements performed on silicon- iron sheets.