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Information × Registration Number 0211U002198, 0109U005156 , R & D reports Title Magnetic properties and nanocrystallization of soft magnetic amorphous alloys obtained by melt spinning technique popup.stage_title Head Kotur Bogdan Yaroslavovich, Registration Date 25-01-2011 Organization Ivan Franko National University of Lviv popup.description2 The samples of the Fe80Si6B14, Fe75Mo5Si6B14, Fe75Mo2.5Co2.5Si6B14, Fe75Mo2.5Mn2.5Si6B14, Fe82Nb2B14Y2, Fe82Nb2B14Gd2, Fe82Nb2B14Dy2, and Fe82Nb2B14Tb2 amorphous alloys (AMA) were produced by the melt spinning method on the cooled substrate. The two stage of the crystallization process and the temperature intervals of the nano- and crystalline phases formation has been determined by the differential scanning calorimetry. The studied AMA were arranged in the following order according to the increase of nanocrystallization temperature: 1) Fe80Si6B14 < Fe75Mo2.5Co2.5Si6B14 < Fe75Mo2.5Mn2.5Si6B14 < Fe75Mo5Si6B14 (722 K, 836 K, 837 K, and 898 K, respectively); 2) Fe82Nb2B14Y2 < Fe82Nb2B14Dy2 < Fe82Nb2B14Gd2 < Fe82Nb2B14Tb2 (807 K, 809 K, 810 K, and 814 K, respectively). The influence of the doping additives on the magnetic properties od AMA, namely Curie temperature, temperature of magnetization, domain's structure, room temperature of magnetostriction, magnetic receptivity of Fe82B14Nb2РЗМ2 type amorphous alloys, has been studied in details. It was shown, that the Було показано, що substitution of the non-magnetic atoms of yttrium on the magnetic atoms of rare-earth (RE) elements (Gd, Dy, and Tb) leads to the increse of the Curie temperature of amorphous phase from the 416 К (Fe82B14Nb2Y2) to 450 К (Fe82B14Nb2Gd2), and also to the decrease of the saturation magnetization (SM= 7 Т). Such changes are connects with formation of the Fe-RE bonds, that develops in the decrease of the value of antiferromagnetic moment on the 1 magnetic from the 2 ?В (Fe82B14Nb2Y2, where Fe is in the amorphous phase) to 1,51 ?В (Fe82B14Nb2Tb2). It was concluded, that the doping additives of Tb and Dy creates a local magnetic anisotropy, which corresponds to the marked decrease of the initial magnetic sensitivity (approximately in 5 times in comparison with Fe82B14Nb2Y2 or Fe82B14Nb2Gd2 alloys), and in 10 times increases a magnetic irreversible effect which was measured at 2 К. In this there appears the regions of the magnetic domains, that do not observes for the Fe82B14Nb2Y2 and Fe82B14Nb2Gd2 amorphous alloys. It was determined, that the most stable to corrosion are Fe82B14Nb2Gd2 and Fe82B14Nb2Tb2 alloys. The annealing at the temperature of first DSC maximum leads to the formation of the passive surface oxide layers, which improves the corrosion properties. The oligomeric coatings have been tested as a defense of the studied AMA from corrosion. It was determined, that the polyfunctional peroxide, which contains a phenyl-radicals and has high affinity to the metallic surface, forms dense coatings and does not decrease relative specific magnetization upon this. 8 Articles and 7 abstracts of the contributions at scientific conferences have been published. The 3 reports have been made at the conferences. Product Description popup.authors Бойчишин Лідія Михайлівна Котур Богдан Ярославович Міка Тарас Мирославович popup.nrat_date 2020-04-02 Close