Effect of mesoscopic magnetomechanical hysteresis on magnetization curves and first-order reversal curve diagrams of magnetoactive elastomers

Magnetoactive elastomers may display magnetic hysteresis even if they are filled only with magnetically soft particles. In this work we discuss application of the FORC analysis to identifying and studying hysteresis of that kind. To obtain theoretical magnetization curves and FORC diagrams for the composites in question, a simple model comprising two magnetically soft particles embedded in an elastic environment is proposed. Elucidation of the features present in FORC diagrams is conducted by means of computer simulation. Despite simplicity of the model, it allows one to explain the origin of diagonal ''ridge'' patterns, which turn up in the FORC diagrams of elastomer composites with magnetically soft filler, and to quantify the experimental results. As the ridge pattern of the diagrams is inherent exclusively to such type of materials, it could be useful for their diagnostics.