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Information × Registration Number 0221U101220, 0119U001230 , R & D reports Title Magneto-electric, magneto-mechanical and magneto-optical properties of structured meso- and nanomagnetic systems popup.stage_title Head Gorobets Yuriy I., Доктор фізико-математичних наук Registration Date 18-01-2021 Organization Institute of Magnetism NAS of Ukraine and MES of Ukraine popup.description2 The subject of research at this stage of research is composite magnetic heterogeneous nanostructures, magnetoactive elastomers based on ferromagnetic micro- and nanoparticles, metal films with low coercive force and high magnetic susceptibility. MAE with nanoparticles of nonstoichiometric manganese La0.8Ag0.2Mn1.2O3-δ with Curie temperature TC = 308 K, slightly higher than room temperature was obtained. It was found that La0.8Ag0.2Mn1.2O3-δ nanoparticles in MAE are magnetized superparamagnetically from room temperature to the Curie point. The coercivity in MAE is about 10 E at room temperature. In the La0.8Ag0.2Mn1.2O3-δ nanopowder, the coercivity is higher due to the closer arrangement of the particles from each other and the greater possibility of interaction by means of magnetic dipole-dipole forces. It is established that the bending of MAE with nanoparticles can be observed starting from small values of the magnetic field. Nanoparticles are more mobile in the elastomer matrix. Therefore, MAE can be restructured even in a small and weakly inhomogeneous magnetic field. Increasing the concentration of magnetized nanoparticles on one of the surfaces of the sample due to the adjustment creates additional mechanical stress, which compresses this surface, which contributes to bending. structures; It is shown that the magnitude of the MAE bending induced by the magnetic field has a temperature characteristic that changes abnormally (critically) near the Curie point during the transition to the paramagnetic state of the particles. When MAE is heated above the Curie point, the magnetoelastic properties of the nanoparticles disappear. When cooled below the Curie point, they are restored. Thus, the opening of another new process of self-control in the IEA may also be interesting from an applied point of view. The new temperature feature of MAE magnetoelasticity with nanoparticles discovered by us is of interest from the point of view of practical applications. The effect   Product Description popup.authors Derecha Dmitriy O. Dzshezsherya Yuriy I. Kalita Volodymyr M. Skirta Yurii B Cherepov Serhii V. popup.nrat_date 2021-01-18 Close