ИСТИНА

Magnetoactive elastomers – MAE – refer to composite materials that consist of polymer matrix and magnetic micro- or nanoparticles. Properties of MAE strongly depend on the type of particles and elastic modulus of polymer matric as well as particle distribution inside the matrix, namely, on the interaction between particles. Hysteresis loops of MAE usually show the process of magnetization of particles inside polymer matrix and the effect of particles spatial distribution. Meanwhile, method of FORC-analysis can provide not only consideration of magnetization process but information about local switching fields, coercivity distribution and local interaction fields. In the frame of the model of elastic coupling between various types of particles, simulation of the magnetization curves and FORC-diagrams of the composites was carried out. To calculate particle redistribution in the system molecular dynamic approach was used. Verlet integration was used to calculate position of particles, dipole-dipole interaction between one type of particles and viscoelastic interaction (Kelvin model) between all types of particles were taken into account. In the model bulk system consists of up to 105 particles, moreover, the FM, FE and polymer particles were used in the sample. To avoid the problem of unsaturation of intermediate FORC-curves, the saturation state of the system was fixed. The system was smoothly brought to the new value of the return field. At that point the number of iterations was increased for additional relaxation of the system. For simulation of the presented model and visualization of the system tool was designed using C++ and Python programming languages.