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Information × Registration Number 0222U002855, 0117U001266 , R & D reports Title The formation and study of magnetic nanomaterials for sensitive magnetic field sensors, functioning on the basis of thermomagnetic and galvanomagnetic effects popup.stage_title Head Kurapov Yurii A., Кандидат технічних наук Registration Date 16-02-2022 Organization E.O.Paton Elektric Welding Institute National Academy of scinces of Ukraine popup.description2  The objects of the study were composite films of ferromagnetic nanocomposites Al2O3-Co and SiO2-Co, obtained by electron beam evaporation and vacuum deposition (EB-PVD). The aim of the work was to study the conditions for the formation of granular and layered ferromagnetic nanocomposites (FMNC) based on ferromagnetic nanoparticles and ferromagnetic layers separated by dielectric matrices. The conditions for the formation of the structure of structurally suitable FMNK films under electron beam deposition in vacuum are generalized. The influence of technological parameters of the molding process - the substrate temperature and the amount of metal phase on the size of metal nanoparticles in the matrix of alumina was studied. The obtained data testify to the possibility of controlled formation of FMNK with nanoparticles of a given size. The optimal technological parameters of Al2O3-Co and SiO2-Co production with the best functional characteristics are determined - growth rate - 0.4… 1.5 μm / min. 0.2… 0.5 μm / min., Thickness 1… 6 μm and 0.8… 3 μm, temperature of the ceramic substrate - 50… 200 ° C. The influence of the technological magnetic field during the formation of FMNK on the percolation threshold of their electrical properties is proved. The phenomenon of magnetic thermoEMF - up to 2.5 mV / K at a temperature of 100 K. According to the results of the research, the application of the EB-PVD method for technologically controlled formation of FMNK with a stable magnetoresistive effect is substantiated. Significance of the work: it is shown that FMNCs can be synthesized in a controlled manner by EB-PVD and are structurally suitable materials with special physical properties. Conclusion: scientific principles of controlled formation of FMNC with stable magnetoresistive effect have been developed, FMNC obtained on ceramic substrates can be used as magnetic field sensors that maintain functional stability at low (up to 77 K) temperatures. Product Description popup.authors Krushynsʹka Larysa A. Lytvyn Stanislav Ye. Stelmakh Yaroslav A. popup.nrat_date 2022-03-09 Close