| MAGNETIC PROPERTIES AND APPLICATIONS OF IRON OXIDES NANOPOWDERS OBTAINED BY THE ELECTRO-EROSION DISPERSION AND SINTERED FROM THEM BULKS AT HIGH-PRESSURE Tetiana Prikhna1; Mykola Monastyrov2; Bernd Büchner3; Fernand D. S. Marquis4; Florian Kongoli5; Sebastian Gaß3; Aniruddha Sathyadharma Prasad3; Ivan Soldatov3; Pavel Potapov3; Kai Neufeld3; Vitaliy Romaka3; Lars Giebeler3; Valeriy Shatilo6; Myroslav Karpets7; Anja Wolter Giraud3; Alexander Borimskiy8; 1V. BAKUL INSTITUTE NASU, Kiev, Ukraine; 2OPEN INTERNATIONAL UNIVERSITY OF HUMAN DEVELOPMENT UKRAINE, Kiev, Ukraine; 3LEIBNIZ-INSTITUT FüR FESTKöRPER- UND WERKSTOFFFORSCHUNG DRESDEN E. V., Dresden, Germany; 4UNITED NANO TECHNOLOGIES (UNT) AND INTEGRATED MATERIALS TECHNOLOGIES AND SYSTEMS (IMTS), Rapid City, United States; 5FLOGEN TECHNOLOGIES, Mont-Royal, Canada; 6D.F. CHEBOTARYOV INSTITUTE OF GERONTOLOGY OF THE NATIONAL ACADEMY OF MEDICAL SCIENCES OF UKRAINE, Kyiv, Ukraine; 7INSTITUTE FOR SUPERHARD MATERIALS, Kiev, Ukraine; 8V. BAKUL INSTITUTE FOR SUPERHARD MATERIALS OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE, Kyiv, Ukraine; PAPER: 394/AdvancedMaterials/Regular (Oral) SCHEDULED: 15:15/Mon. 28 Nov. 2022/Saitong ABSTRACT: Nanodispersed iron oxides obtained by us using the electroerosion dispersion (EED) technology [1, 2] have a wide range of applications. The EED method can be used for recycling of metals chips and granules. The polyvalent nanopowders of iron oxides due to magnetic characteristics, in particular, are successfully used in medicine for blood thinning and as antianemic specimen of prolonged action to saturate the blood with oxygen and maintain saturation at the optimal level for human life; in animal husbandry as feed additives to accelerate the growth of livestock and in increasing the laying capacity of birds. In 2020-2021 the dietary supplement "Lisoferrin" and feed additive "Nano-Fe" were developed and certified in Ukraine, although the mechanism of their action the appertaining processes remain not fully understood. It has been observed that the developed nanopowders of iron oxides also have a positive effect on the treatment of a wide range of other diseases, such as: related to dementia, cognitive disorders, contribute to the reduction of blood sugar levels, accelerate the healing of purulent wounds in varicose veins and the fusion of broken bones, etc. In addition, the developed nanopowders are characterized by a high ability to absorb ultra-high-frequency radiation (higher than the commercial powders of iron oxide ‟Magsilica”, produced in Germany) [1], and are therefore promising for the production of shielding which absorb ultrahigh frequency electromagnetic radiation. The iron oxide nanopowders developed in this research have a high adsorption capacity in relation to heavy metal ions [3] and are promising for water purification and wastewater treatment [3, 4]. From the point of view of magnetic properties, they are close to soft magnetic materials and demonstrate superparamagnetic behavior [1]. The bulk materials consolidated from the Fe-O nano powders under high pressure conditions (using 2 GPa pressure at 1200 and 1300 °C for 0.07 h in contact with hexagonal boron nitride) also exhibited soft magnetic behavior, which makes their use very promising in electrical engineering and in other branches of industrial technology. The structure of sintered materials was investigated by X-ray diffraction with Rietveld refinement and showed that the materials consolidated under 2 GPa at 900 and 1000 °C contained 75–80 wt.% FeO and 25–20 wt.% Fe, and the materials sintered at 1100 <sup>o</sup>C, in parallel with 32 wt. % FeO and 2 wt.% Fe was present contained a significant amount of Fe<sub>3</sub>N: 66 wt.%. However, the structure of the same materials consolidated at 1200-1300 °C contained about 100% of the Fe<sub>3</sub>N phase. Thus, under conditions of high pressures and temperatures with increasing sintering temperature, reduction of iron oxide was observed, followed by its nitriding with nitrogen released from the boron nitride, which led to improvement of soft magnetic characteristics of sintered materials. References: [1] B. Halbedel, T. Prikhna, P. Quiroz, T. Kups, M. Monastyrov, Current Applied Physics, 18(11) (2018) 1410–1414. [2] M.K. Monastyrov, T.A. Prikhna, A.G. Mamalis, W. Gawalek, P.M. Talanchuk, R.V. Shekera Nanotechnology Perceptions, 4 (2008) 179–187. [3] M. Monastyrov, T. Prikhna, B. Halbedel, A.G. Mamalis, O. Prysiazhna, Nanotechnology Perceptions. 15(1) (2019) 48–57. N24MO18A [4] G. Kochetov, T. Prikhna, D. Samchenko, O. Prysiazhna, M. Monastyrov, V. Moshchil, A. Mamalis, Nanotechnology Perceptions, 17(1) (2021) 9–12. |
