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Information × Registration Number 0226U000564, (0124U000455) , R & D reports Title Magnetoelastic effects and magnetic field induced critical deformations of magnetoactive elastomers popup.stage_title Виготовлення зразків МАЕ і дослідження їх магнітних властивостей Head Dzhezherya Yuriy Іvanovich, Доктор фізико-математичних наук Registration Date 12-01-2026 Organization V.G. Baryakhtar Institute of Magnetism of the National Academy of Sciences of Ukraine (IMag NAS of Ukraine) popup.description1 The purpose of the project is to study the effects of magnetoelasticity and critical deformation phenomena of magnetoactive elastomers caused by their magnetization and moderate thermal effects, which are caused by the samples shape anisotropy, induced material anisotropy, and phase transitions in the magnetic filler of magnetoactive elastomers. popup.description2 A new effect of equilibrium kink-like torsion deformation formation in a beam with a magnetic field in a uniform magnetic field has been theoretically predicted and experimentally confirmed. It has been established that the kink is a transition region between two homogeneous undeformed states and is caused by the compensation of elastic and magnetoelastic moments when the magnetization and the external field are non-collinear. It is shown that a heterogeneously deformed low-symmetry magnetic state is realized in the kink region, while outside the kink the beam is in a homogeneous high-symmetry state with collinear magnetization. The reversible nature of the effect with a jump-like disappearance of the kink when the magnetic field is turned off at a finite (critical) field value has been experimentally proven. The synthesis and comprehensive study of the structural, magnetic, and thermal properties of CaFeO2 nanoparticles obtained by the sol-gel method were carried out. X-ray structural analysis confirmed the formation of a single-phase orthorhombic oxygen-deficient perovskite-like structure. A transition from a ferromagnetic to a superparamagnetic state with complete disappearance of coercivity at T ≈ 250 К was established. The Curie temperature of CaFeO2 was determined to be approximately 625 К. For the first time for CaFeO2 nanoparticles, the efficiency of magnetic heating in an alternating magnetic field with a frequency of 300 kHz was experimentally investigated. It has been shown that CaFeO2 aqueous suspensions exhibit a pronounced thermal effect at field amplitudes above 6,5 mT, with the saturation temperature and specific power loss increasing with increasing field amplitude and nanoparticle concentration, reaching values above 30 kW/kg. Product Description popup.authors Igor V. Gerasimchuk Yurii B. Skyrta Oleksiy V. Pashchenko Serhii O. Reshetniak Serhii V. Cherepov Viktor M. Kalіta popup.nrat_date 2026-01-12 Close