A phenomenological magnetomechanical model for hysteresis loops
In this work we propose a simple phenomenological model for magnetization curves of stressed samples. The effect of stress is introduced by scaling the arctangent function argument (magnetic field) proportionally to stress. The magnetization curve is modelled by one or two arctangent functions. Despite of its simplicity, the model gives a very good agreement with experimental curves, reproducing all stress-induced features usually observed on the magnetization curves including the common crossover point and constricted hysteresis loops. The popular effective field concept in this model is just a consequence of a simple scaling of the magnetic field. We show that the differential susceptibility is inversely proportional to the applied stress for all magnetization values. We propose to analyze the field and differential susceptibility as a function of magnetization in contrast to convenient M(H) loops.