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Проведен анализ влияния Ti, Mo и W на характер аморфной нано- и кристаллической структуры на прочностные и кинетические характеристики - диффузии D и проницаемости Ф водорода в мембранных сплавах, созданных на основе бинарных Ni - Nb и V - Ni. Легирование сплавов Ni - V титаном, молибденом и вольфрамом ведет к постепенному замещению ими ниобия и ванадия и способствует образованию нескольких второстепенных фаз хотя и действующих как барьеры для диффузии водорода, но способствующих снижению процессов гидридообразования. Выявлена строгая зависимость кинетики водорода не только от термодинамических параметров -температуры и давления, но и от наличия свободного объема в формируемых аморфных, нано-кристаллических и кристаллических сплавов. Установлено, что процессы селективности, динамика водорода - его поток J, определяемый произведением диффузии и проницаемости (J = D×Ф), зависят от базового состава, выбора легирующих элементов (Ti,Mo и W ), а также формируемых структур - аморфной, нанокристаллической и полифазной дуплексной кристаллической микроструктурой. Установлено, что тщательно подобранный состав определяет производительность селективного процесса и способствует выделению высокочистого водорода с последующими его приложениями для зеленой энергетики. An analysis was carried out of influence of Ti, Mo and W on the nature of the amorphous nano- and crystalline structures on the strength and kinetic characteristics - diffusion D and permeability Ф of hydrogen in membrane alloys based on binary Nb - Ni, V - Ni. Doping with Nb - V alloys, titanium, molybdenum and tungsten leads to the gradual replacement of niobium and vanadium, and promotes the formation of several minor phases while acting as barriers for hydrogen diffusion, but contributing hydride reduction processes. A close dependence of the hydrogen kinetics was revealed not only on thermodynamic parameters - temperature and pressure, but also on the presence of free volume in the formed amorphous, nanocrystalline and crystalline alloys. So, the processes of selectivity, the dynamics of hydrogen - its flux J determined by the product of diffusion D and permeability Ф, J = D×Ф depend on the basic composition and the choice of alloying elements (Ti,Mo and W ), as well as the formed structures - amorphous, nanocrystalline and duplex, represented by multiphase crystalline microstructures. It was found that a carefully selected composition determines the productivity of the selective process and promotes the release of high-purity hydrogen with its subsequent applications for green energy.

Аморфные, нанокристаллические мембранные сплавы на основе элементов V группы с уникальными механическими и функциональными свойствами и с матричной дуплексной микроструктурой активно способствуют развитию водородной энергетики. Имеются еще не вполне разрешенные проблемы для этих новых сплавов -их низкая термическая стабильность, недосточная механическая прочность (пластичность, твердость), а также охрупчивание интерметаллидное и гидридное. Для эффективного применения разрабатываются сплавы с тройным составом - в которые помимо элементов V группы входят и легирующие металлы никель и титан. Получают не только аморфные и нанокристаллические сплавы, применимые в электронике и электроэнергетике, а также мембранные сплавы с дуплексной матричной структурой, объединяющей аморфные, так нано- и квазикристаллические дендритно упрочняющие фазы, как упрочняющие аморфную матрицу. В специализируемых мембранных тройных сплавах формируются соединения NiTi и NiTi, стабилизирующие и предохраняющие нано- и кристаллические мембраны от хрупкого разрушения. Установлено, что интенсивное образование гидридов в этих альтернативных мембранных сплавах столь же не желательно, как и для традиционных сплавов на основе палладия. Рассматриваемые сплавы действительно позволяют получить газообразный водород высокой чистоты с применением новых составов взамен дорогостоящих мембран на основе сплавов Pd - Au / Ag / Cu. With unique mechanical and functional properties, amorphous, nanocrystalline and matrix duplex microstructure membrane alloys based on group V elements actively contribute to the development of hydrogen energy. There are still not completely resolved problems for these new alloys - their low thermal stability, insufficient mechanical strength (plasticity, hardness), and intermetallic and hydride embrittlement. For effective use, alloys with a triple composition are being developed - which, in addition to the elements of group V, also include nickel and titanium as alloying metals. Not only amorphous and nanocrystalline alloys are obtained that are applicable in electronics and power engineering, as well as membrane alloys with a duplex matrix structure that combines amorphous, nano-and quasicrystalline dendritic-hardening phases strengthening the amorphous matrix. In specialized membrane ternary alloys, NiTi and NiTi compounds are formed, which stabilize and protect nano-and crystalline membranes from brittle destruction. It has been found that the intense formation of hydrides in these alternative membrane alloys is as undesirable as for palladium-based compounds. The alloys under consideration actually make it possible to obtain high-purity gaseous hydrogen using new compositions instead of expensive membranes based on Pd - Au / Ag / Cu alloys.

Intermetallic phases in the Fe-Nb system have been obtained as products of the devitrification of a homogeneous amorphous Fe70Nb30 alloy prepared by mechanical alloying. Besides Fe2Nb Laves and Fe7Nb6 intermetallic phases, α-Fe phase has been detected by X-ray diffraction (XRD). Hyperfine parameters for both Fe2Nb and Fe7Nb6 intermetallics have been obtained from Mössbauer spectroscopy in correlation with phase identification from XRD results. Thermomagnetic measurements show changes in the Curie temperatures of the amorphous and Fe2Nb phases during the crystallization, due to compositional variations related to the developing of the α-Fe phase. Kinetics of the crystallization process has been analyzed using the classical Johnson-Mehl-Avrami-Kolmogorov kinetic theory in both isothermal and non-isothermal regimes. European Commission MAT 2016-77265-R

Intermetallic phases in the Fe-Nb system have been obtained as products of the devitrification of a homogeneous amorphous Fe70Nb30 alloy prepared by mechanical alloying. Besides Fe2Nb Laves and Fe7Nb6 intermetallic phases, α-Fe phase has been detected by X-ray diffraction (XRD). Hyperfine parameters for both Fe2Nb and Fe7Nb6 intermetallics have been obtained from Mossbauer spectroscopy in correlation with phase identification from XRD results. Thermomagnetic measurements show changes in the Curie temperatures of the amorphous and Fe2Nb phases during the crystallization, due to compositional variations related to the developing of the α-Fe phase. Kinetics of the crystallization process has been analyzed using the classical Johnson-Mehl-Avrami-Kolmogorov kinetic theory in both isothermal and non-isothermal regimes.

Magnetic properties of functional magnetic materials depend on the magnetization processes nature. Creation of amorphous and nanocrystalline alloys using the rapid quenching technology is the result of the latest advances in magnetic materials area. Although significantly different in structure, they show excellence properties. In this paper we will investigate the magnetization properties of the Finemet-type nanocrystalline alloys in the range of their initial permeability formation. We will show that due to low level of effective magnetic anisotropy, even in weak fields, magnetization can occur through reversible, hysteresis-free rotation of the domain's magnetization vector. © Published under licence by IOP Publishing Ltd. Ministry of Science and Higher Education of the Russian Federation: 3.6121.2017/8.9, 4.9541.2017/8.9 This work was supported by the Ministry of Science and higher Education and of the Russian Federation in the framework of state tasks No. 3.6121.2017/8.9 and No. 4.9541.2017/8.9.

Amorphous Fe75Nb10B15 and (Fe70Co30)75Nb10B15 alloys were prepared by mechanical alloying from the elemental constituents and hot compacted at different temperatures within the supercooled liquid region. After compaction, the microstructure studied by X-ray diffraction shows an increase in the crystalline fraction for both compositions. Magnetic properties and magnetic entropy change of compacted samples of the Co-free alloy were enhanced with respect to the powder sample, meanwhile, a deterioration in these properties was observed for the Co containing alloy after compaction. Both changes could be ascribed to an enrichment in boron in the amorphous phase. Ministerio de Ciencia e Innovación MAT2013-45165-P European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER) MAT2013-45165-P

The magnetic and structural properties of amorphous Fe40Ni39Mo4B18 alloy which is a precursor of new nanocrystalline material have been investigated. Differential scanning calorimetry (DSC) and the temperature dependence of resistivity were used to determine the structural stability and the crystallization temperatures. It was shown that amorphous FeNiMoB alloy crystallizes in two stages. Firstly at the temperature 360 degreesC, the FeNi phase appears, secondly at about 450 degreesC FeNiMo borides crystallize. The temperature dependence of the initial susceptibility describes the evolution of the magnetic properties in an amorphous state as well as during nano crystallization; the Curie temperature was found to be 327 degreesC. The magnetic after-effect (MAE) was also studied. The MAE spectrum consists of a thermally activated peak at 200 degreesC. The activation energy spectra (AES) were determined from the MAE by means of a computer analysis.

Influence of thermal and thermomagnetic treatments conditions on the magnetic properties and time-temperature stability of amorphous and nanocrystalline alloys based on Fe and Co with additions of Mo, Hf, Zr was studied. It was established that the nanocrystallization in an alternating magnetic field of modified amorphous alloys based on Fe and Co improved significantly their static and dynamic properties and maintained the high thermal stability of the properties. Досліджено вплив умов термічних і термомагнітних обробок на магнітні властивості і температурно-часову стабільність аморфних і нанокристалічних сплавів на основі Fe і Co з домішками Mo, Hf, Zr. Встановлено, що нанокристалізація у змінному магнітному полі модифікованих аморфних сплавів на основі Fe і Co істотно покращує їх статичні і динамічні властивості, зберігаючи високу температурну стабільність властивостей. Исследовано влияние условий термических и термомагнитных обработок на магнитные свойства и температурно-временную стабильность аморфных и нанокристаллических сплавов на основе Fe и Co с добавками Mo, Hf, Zr. Установлено, что нанокристаллизация в переменном магнитном поле модифицированных аморфных сплавов на основе Fe и Co существенно улучшает их статические и динамические свойства, сохраняя высокую температурную стабильность свойств.

The milling time evolution of magnetic anisotropy of ball milled powders can be described considering two regimes. First, for short milling times, the main factor affecting the magnetic behavior of the alloy is the accumulation of internal stresses. Second, for long milling times, magnetic anisotropy can be explained using three contributions: long-range magnetoelastic, averaged short-range magnetoelastic and averaged magnetocrystalline anisotropies. Ministerio de Ciencia, Innovación y Universidades MAT2007-65227 European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER) MAT2007-65227

Purpose: In the present paper, the kinetics of crystallization process and its correlation with magnetic properties of the Co80Si9B11 alloy was carefully examined. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD), electrical resistivity in situ measurements (four-point probe), saturation magnetization in situ measurements (magnetic balance) and initial relative magnetic permeability measurements (Maxwell-Wien bridge). Findings: The investigations proved that thermal annealing of amorphous Co80Si9B11 alloy leads to a crystallization process and radical changes of magnetic properties. The activation energy of this process was determined as Ec=3.0±0.2 eV. Research limitations/implications: According to the results presented in the present paper the examined alloys can be used as a very good soft magnetic material. Originality/value: The best soft magnetic properties are observed in as quenched state.

The magnetic and structural properties of amorphous Fe40Ni39Mo4B18 alloy which is a precursor of new nanocrystalline material have been investigated. Differential scanning calorimetry (DSC) and the temperature dependence of resistivity were used to determine the structural stability and the crystallization temperatures. It was shown that amorphous FeNiMoB alloy crystallizes in two stages. Firstly at the temperature 360 degreesC, the FeNi phase appears, secondly at about 450 degreesC FeNiMo borides crystallize. The temperature dependence of the initial susceptibility describes the evolution of the magnetic properties in an amorphous state as well as during nano crystallization; the Curie temperature was found to be 327 degreesC. The magnetic after-effect (MAE) was also studied. The MAE spectrum consists of a thermally activated peak at 200 degreesC. The activation energy spectra (AES) were determined from the MAE by means of a computer analysis.

The magnetic and structural properties of amorphous Fe40Ni39Mo4B18 alloy which is a precursor of new nanocrystalline material have been investigated.Differential scanning calorimetry (DSC) and the temperature dependence of resistivity were used to determine the structural stability and the crystallization temperatures. It was shown that amorphous FeNiMoB alloy crystallizes in two stages. Firstly at the temperature 360 degreesC, the FeNi phase appears, secondly at about 450 degreesC FeNiMo borides crystallize. The temperature dependence of the initial susceptibility describes the evolution of the magnetic properties in an amorphous state as well as during nano crystallization; the Curie temperature was found to be 327 degreesC.The magnetic after-effect (MAE) was also studied. The MAE spectrum consists of a thermally activated peak at 200 degreesC. The activation energy spectra (AES) were determined from the MAE by means of a computer analysis.