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The synthesis of intermetallic material was carried out by means of dehydrogenating annealing of a (TiH 2) 30 Zr 45 Ni 25 sample in vacuum by an electron beam. The properties of the obtained material were studied for establishing the structural phase composition by scanning electron microscopy and X-ray structural analysis. It was found that prolonged exposure of an electron beam to a sample containing titanium hydride leads to a number of structural transformations in the material, accompanied by a redistribution of hydrogen from titanium to zirconium and culminating in the synthesis of a ternary alloy with characteristic growth structures. The processes of hydrogen sorption-desorption by a synthesized sample were studied, the temperature ranges of these processes and the absorption capacity of the obtained material were established. It was shown that the structure of the sample formed upon heating by an electron beam promotes the absorption of hydrogen at room temperature up to 1.41 wt.%.
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198 ISSN 1562-6016. ВАНТ. 2020. №1(125)
UDC 544.723; 669.788
SYNTHESIS OF HYDROGEN STORAGE MATERIALS IN A Ti-Zr-Ni
SYSTEM USING THE HYDRIDE CYCLE TECHNOLOGY DURING
DEHYDROGENATION BY AN ELECTRON BEAM IN A VACUUM
O.E. Dmytrenko, V.I. Dubinko, V.M. Borysenko, K. Irwin*
National Science Center “Kharkоv Institute of Physics and Technology”, Kharkiv, Ukraine;
*Quantum Gravity Research, Los Angeles, CA
E-mail: dmitrenko@kipt.kharkov.ua
The synthesis of intermetallic material was carried out by means of dehydrogenating annealing of a
(TiH2)30Zr45Ni25 sample in vacuum by an electron beam. The properties of the obtained material were studied for
establishing the structural phase composition by scanning electron microscopy and X-ray structural analysis. It was
found that prolonged exposure of an electron beam to a sample containing titanium hydride leads to a number of
structural transformations in the material, accompanied by a redistribution of hydrogen from titanium to zirconium
and culminating in the synthesis of a ternary alloy with characteristic growth structures. The processes of hydrogen
sorption-desorption by a synthesized sample were studied, the temperature ranges of these processes and the
absorption capacity of the obtained material were established. It was shown that the structure of the sample formed
upon heating by an electron beam promotes the absorption of hydrogen at room temperature up to 1.41 wt.%.
INTRODUCTION
The possibility of synthesizing complex
intermetallic and quasicrystalline materials based on
refractory metals of the zirconium group using hydride
technology was shown in [18]. These materials are
capable of reversibly absorbing hydrogen in significant
quantities over 2 wt.% [911], which allows us to
consider them as materials for the storage of hydrogen.
The studies conducted earlier [12, 13] showed that
materials of the Ti-Zr-Ni system obtained by the rapid
quenching method and containing the Laves phase C14
(L-TiZrNi) absorb hydrogen in the temperature range
450550 °С. The maximum amount of hydrogen when
saturated from the gas phase occurs at 450 °C and is
characterized by slow sorption to values of about
1.8 wt.%. For the industrial use of these materials as
hydrogen storage devices, it is necessary to increase the
absorption coefficient and reduce the sorption-
desorption temperatures. In addition, the synthesis of
samples by spinning is inefficient and technically
complex, requires the use of expensive vacuum
equipment. Therefore, it is necessary to develop more
productive techniques that allow the synthesis of bulk
samples with a given structure and properties. In this
work, we studied the structure and properties of the
(TiH2)30Zr45Ni25 sample during its layer-by-layer
dehydrogenation in a vacuum under the influence of an
electron beam. The technology of the hydride cycle,
based on the interaction of the decomposition products
(dissociation) of the hydrides of the initial components
with the formation of systems and phases characteristic
of these materials with significantly less energy
consumption. Hydrogen, in this case, plays the role of a
temporary alloying impurity to titanium and zirconium,
leaving the sample when heated in a vacuum, but
having a positive effect on the process of converting the
system of starting dispersed particles into a massive
(consolidated) alloy. Titanium and zirconium, as
elements of one group of the periodic system, have
similar characteristics of interaction with hydrogen, in
particular, they have similar binary phase diagrams with
hydrogen (both metals form hydrides).
Dehydrogenation with an electron beam will allow
gradient heating of the sample and, therefore, obtain a
sample with all intermediate structural states from
hydride to ternary alloy. And, therefore, with a cross-
section, it will allow studying/observe these processes
of structural transformations, which in turn will expand
the possibilities of synthesis of materials of the Ti-Zr-Ni
system with predetermined properties.
MATERIALS AND METHODS
To prepare the sample (TiH2)30Zr45Ni25 (wt.%), the
powders of the starting components were used: TiH2
(with a hydrogen content of 3.8 wt.%, Zr powder
(ПЦРК-1) Ni powder (ПНЭ-1)). The powders were
mixed by grinding in an alundum mortar for 10 min.
The resulting mixture powders were pressed into a
briquette of Ø 30 mm and a height of 15 mm with a load
of 77 t.
Annealing/dehydrogenation of the sample was
carried out by an electron beam in a high vacuum at the
EBM-1 facility [14]. Electron beam treatment of the
sample (TiH2)30Zr45Ni25 was carried out in vacuum
(1…5)·10-2 Pa. The structure and composition of the
samples were studied by scanning electron microscopy
(SEM) and X-ray energy-dispersive microanalysis
(EDX), using a SEM JSM 7001F with an accelerating
voltage of 20 kV. Observation of the structure was
carried out both in the secondary electron (SEI) mode
and in the backscattered electron (COMPO) mode
forming the composite image contrast. The composition
was analyzed using the INCA PentaFET*3 detector and
the Oxford Instruments INCA 4.11 program.
Diffractometric studies of the samples were carried out
on a DRON-4-07 X-ray diffractometer in copper Cu-
radiation using a selectively absorbing β-filter.
Diffracted radiation was recorded by a scintillation
detector. The diffraction patterns were taken in step
mode. The following samples of composition
(TiH2)30Zr45Ni25 were taken for research: a) the melted
ISSN 1562-6016. ВАНТ. 2020. №1(125) 199
part; b) not melted part. The samples were saturated
with hydrogen from the gas phase in two different
chambers: a) a metal chamber with a vacuum pumping
system and a hydrogen/deuterium supply system with a
pressure of up to 3 atm; b) in an installation with an
MX7203 mass spectrometer at a hydrogen pressure of
10 mm Hg and heating in the range of 20450 °C for 3
h. The temperature increased at a rate of 5 °C/min in a
hydrogen atmosphere. The temperature difference at the
boundaries of the heat treatment region is ± 20 °C. The
cooling of the furnace to 20 °C took place in a hydrogen
atmosphere. Hydrogen-saturated samples of Ti-Zr-Ni
alloys were investigated for desorption by heating in a
vacuum in the temperature range 0900 °C using a
setup with an MX7203 mass spectrometer. The
MX7203 mass spectrometer is designed to determine
the hydrogen in the alloys and the composition of the
gas phase released from the material when heated in a
vacuum.
RESULTS AND DISCUSSION
The sample obtained after electron beam melting
was partially melted: the upper part of the briquette was
melted to a depth of 4 mm. The rest of the briquette is
not fused, it easily crumbles with little effort. For
analysis of XRD, the upper (melted) and lower (non-
melted) parts of the sample were taken, which were
mechanically fragmented into several parts (the
resulting sample is extremely fragile and easily
collapses upon impact). For SEM/EDX studies, a
transverse kink of the sample was used, thus the
structure from the molten surface to the unsintered
powders was analyzed. Electron microscopy showed
that there is a significant structural heterogeneity along
with the depth of the sample.
Under the influence of an electron beam, the gradual
heating of the sample begins. Since the sample is
located on a copper water-cooled crystallizer, and the
electron beams are focused on the upper surface of the
sample, a heat gradient arises from the top-down of the
sample. With further heating of the upper surface and
reaching the dissociation temperature of titanium
hydride, the process of sequential decomposition of
TiH2 begins according to the scheme [15]: TiH2(ε)
TiH2(δ) Ti(β) Ti(α). However, as it was
established during a preliminary study of the thermal
desorption of TiH2 shown in Fig. 1, the active
decomposition of titanium hydride occurs at a
temperature of 500550 °C, at the same time, at this
temperature, zirconium powder actively absorbs
hydrogen, since the decomposition temperature of ZrH2
is higher than that of TiH2 at 100150 °С (see Fig. 1).
Thus, the heating of the (TiH2)30Zr45Ni25 sample by
an electron beam is accompanied by a series of
structural transformations that occur during the
redistribution of hydrogen from TiH2 to ZrH2 and the
subsequent decomposition of ZrH2(ε) ZrH2(δ)
Zr(β) Zr(α) with increasing temperature [16]. Since
the beam power is set necessary for slow heating of the
sample and does not change further, a stationary
dehydrogenation process is established in the chamber
in which the above transformations occur layer by layer,
as the sample is heated from top to bottom. During
dissociation during annealing in vacuum, TiH2 and ZrH2
emit hydrogen, gradually turning into metals, and a
decrease in the concentration of hydrogen in their
crystal lattices leads to a sequence of phase
transformations. Due to the presence of bonds broken
during dissociation, the obtained metal titanium and
zirconium actively interact with each other and with
nickel at temperatures well below their melting points.
An additional factor contributing to the interaction is the
cleaning of the surfaces of the powders from oxide films
by active hydrogen released during the decomposition
of hydrides, as shown in [17].
0
10
20
30
40
50
60
70
80
90
100
0100 200 300 400 500 600 700 800
Temperature, °С
Pressure, mm.Hg.
TiH2
ZrH2
Fig. 1. Thermal desorption TiH2 and ZrH2
The fusion process begins with the local melting of
individual Ti, Zr, Ni particles at the contact boundary
with the formation of the eutectic (Fig. 2,a). As the
sample is heated and the temperature rises in volume,
the local boundary fusion passes into the melt zones
with the involvement of a larger number of initial
components. The resulting eutectic type melt (since a
composition close to the eutectic is taken) penetrates
deep into the sample, the melt zone expands (see
Fig. 2,b). When an equilibrium annealing process is
established (all heat transferred to the upper part of the
sample by an electron beam is removed through the
lower part of the sample located on a copper water-
cooled tray), a new/gradual formation of a new structure
in the melt zone occurs.
At a certain point in time (at a certain temperature,
composition, temperature gradient), more refractory
crystallization centers form in the melt (see Fig. 2,c).
Since this composition of the Ti-Zr-Ni melt corresponds
to eutectic, and the temperature at the beginning of
crystallization, we obtain a mixture of more refractory
crystals, presumably enriched with zirconium,
surrounded by more fusible melts with a high content of
titanium and nickel (see Fig. 2,d). This was confirmed
by the EDX analysis data presented in Table. The Zr
content in the growth structures is 56 wt.%, in contrast
to 4345 wt.% in the eutectic matrix surrounding them.
Classical eutectic precipitation will not occur since the
sample continues to be heated by the electron beam and
the melt zone continues to propagate down the sample.
200 ISSN 1562-6016. ВАНТ. 2020. №1(125)
a
c
e
Fig. 2. Formation of growth patterns characteristic of the given system with gradual melting of the sample
After the equilibrium process is established, with a
constant beam power that corresponds to the melting
point of the eutectic and a constant heat removal rate,
i.e., we have a constant temperature gradient, the melt
and crystallization centers create optimal conditions for
polycrystalline grain growth. As can be seen from
Fig. 2,e,f the growth patterns characteristic of this
system are formed. As these formations grow, the
amount of surrounding eutectic decreases accordingly.
At a distance of less than 1 mm from the heated upper
surface of the sample, the crystals completely “absorb”
the surrounding eutectic and grow to the maximum size
limited by neighboring formations. Considering the
duration of the annealing process (about 3 h), significant
formations up to 500 m in size are formed (Fig. 3).
Since the gradual melting of the sample occurs, all
of the above processes occur in layers as the sample is
melted, i.e. simultaneously: in a layer located 3 mm
ISSN 1562-6016. ВАНТ. 2020. №1(125) 201
from the upper part of the sample, crystallization centers
surrounded by a eutectic only appear (see Fig. 2,c,d); in
a layer of 2 mm (from the upper part of the sample)
crystalline multilayer formations (growth figures) have
already formed, partially surrounded by a eutectic (see
Fig. 2,e,f); in a 1 mm layer, crystals completely
absorbing the surrounding eutectic, grow to maximum
sizes (limited by adjacent formations) form spherical
formations consisting of square pyramids and octahedra
(see Fig. 3,a,b); on the surface of the sample (directly
under the electron beam) the previously formed
spherical formations begin to melt due to the gradual
heating of the entire sample (see Fig. 3,c,d).
Data from EDX analysis of growth patterns and surrounding eutectics
Element
Ti K
Ni K
Zr L
Hf L
Totals
Growth patterns
21.73
19.41
56.66
2.20
100.00
Surrounding matrix
31.70
26.07
42.23
100.00
a
b
c
d
Fig. 3. Spherical formations consisting of square pyramids and octahedrons (a, b); reflow of previously formed
spherical formations consisting of square pyramids and octahedrons (c, d)
Thus, the obtained sample contains various
structural elements that are formed during the long-term
exposure of the initial sample (TiH2)30Zr45Ni25 electron
beam. The stages characteristic for each stage can be
distinguished: fusion of the initial components Ti, Zr,
Ni formation of growth structures surrounded by
eutectics conglomerates of square pyramids
fusion of previously formed square pyramids and
octahedrons. An additional factor for the formation of
structural features in this sample is the dissociation of
titanium hydride into hydrogen and titanium. And
accordingly, the active diffusion of released hydrogen in
a sample heated to a pre-melting temperature.
PHASE ANALYSIS OF SAMPLES Ti30Zr45Ni25
X-ray diffraction patterns of the samples are shown
in Fig. 4. The results of studies of the phase
composition of the samples showed that 4 phases were
identified in the melted upper part of the sample (see
Fig. 4,a): (Ti,Zr)2Ni, Laves phase L-TiZrNi, Ti-α, and
Zr-α. The lattice parameter of the (Ti,Zr)2Ni phase is
a = 11.761 Å. The lattice parameters of the Laves phase
are a = 5.222 Å; c = 8.558 Å. The lattice parameters of
titanium are a = 2.964 Å; c = 4.618 Å. The lattice
202 ISSN 1562-6016. ВАНТ. 2020. №1(125)
parameters of zirconium are a = 3.242 Å; c = 5.156 Å.
Due to the superposition of some diffraction lines on
each other, some phases are not identified, including the
quasicrystalline phase.
The presence of three phases was revealed in the
unmelted lower part of the sample (see Fig. 4,b):
tetragonal zirconium hydride ε-ZrH2-x, cubic titanium
hydride TiH2, and nickel Ni. The lattice parameters of
the ε-ZrH2-x phase are: a = 3.496 Å; c = 4.493 Å. The
lattice parameter of titanium hydride TiH2 is
a = 4.411 Å. The lattice parameter of nickel Ni is
a = 3.524 Å. In addition, the sample contains diffraction
lines that could not be indicated.
a
b
Fig. 4. Diffraction pattern of the sample
(TiH2)30Zr45Ni25: upper melted part (a);
lower not melted part (b)
Since there was no zirconium hydride in the initial
sample, therefore, the presence of ZrH2(δ) in the lower
non-melted part of the sample confirms that the
hydrogen formed during the decomposition of titanium
hydride is absorbed by zirconium. And only then, with a
further increase in temperature, does the sample leave.
The presence in the sample of unusual structural
formations shown in Figs. 2, 3 gave a prerequisite for
research on the interaction of this material with
hydrogen.
THE STUDY OF SORPTION-DESORPTION
For conducting research, a sample of the upper
molten portion weighing 2.8 g was previously ground
by grinding in an alundum mortar. Grinding was carried
out immediately before the experiment. After loading
the sample into the reaction chamber, the chamber was
evacuated to a pressure of 510-6 bar. After the
evacuation, hydrogen was introduced into the reaction
chamber. The initial hydrogen pressure in the reaction
chamber was 198 kPa. About 500 s after the hydrogen
was introduced into the reaction chamber, intense heat
evolution began, which led to an increase in the
temperature of the sample (Fig. 5,a). The rate of heat
evolution was proportional to the rate of change in
pressure in the reaction chamber Fig. 5,b. The heat was
generated by pulses. The heat generation impulsivity is
especially pronounced at the initial stage of hydrogen
absorption. When saturated, the sample absorbed about
1.41% by weight of hydrogen for 1.5 h. The relatively
small amount of absorbed hydrogen can be explained by
the predominance of the (Ti,Zr)2Ni phase over the
Laves phase of L-TiZrNi. As was established earlier
[10], the absorption potential of the (Ti,Zr)2Ni phase is
much lower than that of the Laves phase. However, in
contrast to rapidly quenched tapes of the same
composition starting to absorb hydrogen when heated
above 400 °C, this sample began to absorb hydrogen at
12 °C after a short incubation period.
a
b
Fig. 5. Dependences of the temperature of sample (a)
and the pressure in the reaction chamber (b) on time,
when the Ti30Zr45Ni25 sample is saturated with hydrogen
at room temperature
After saturation with hydrogen at room temperature,
the sample was subjected to thermal desorption by
heating to 900 °C and cooling to room temperature with
ISSN 1562-6016. ВАНТ. 2020. №1(125) 203
continuous vacuum pumping. Fig. 6,a shows the
dependence of the pressure in the reaction chamber on
the temperature of the sample during monotonous
heating of the sample at a constant rate of pumping the
reaction chamber to a low vacuum after a heating cycle.
Intensive gas evolution from the sample began at about
40 °C and lasted with variable intensity up to a
temperature of 800 °C. The presence of several peaks of
gas evolution indicates the evolution of hydrogen from
various phases present in the sample, which corresponds
to XRD analysis.
a
b
Fig. 6. The dependence of the pressure in the reaction
chamber on the temperature of the sample when the
sample is heated at a constant rate of evacuation of the
reaction chamber to vacuum after the first
saturation (a), after re-saturation (b)
After degassing, the sample was re-saturated with
hydrogen at room temperature Fig. 7. The initial
hydrogen pressure in the reaction chamber was 260 kPa.
Upon repeated saturation, the absorption of hydrogen by
the sample began with approximately the same delay as
at the first saturation. The heat generation impulsivity
was also observed. The intensity of the heat during the
second saturation was significantly lower, but it took a
longer time. The amount of heat was proportional to the
magnitude of the change in pressure in the reaction
chamber. Upon re-saturation, the sample absorbed
0.34 wt.% hydrogen for 4 h. Thus, it was found that this
material is capable of absorbing hydrogen at room
temperature after a dehydrogenation cycle. Subsequent
dehydrogenation showed identical kinetics of thermal
desorption (see Fig. 6,b).
The next stage of studies on the interaction with
hydrogen was carried out on the subject of the influence
of passivation/oxidation of the surface of the sample by
air. Between grinding material and loading the sample
into the reaction chamber, the crushed material of the
sample (upper melted portion) Ti30Zr45Ni25 was in the
air for 7 days. After loading the sample into the reaction
chamber, the chamber was evacuated to a pressure of
510-6 bar. After the evacuation, hydrogen was
introduced into the reaction chamber. The initial
hydrogen pressure in the chamber was 268 kPa. As a
result of the exposure of the sample at room temperature
for 60 min, hydrogen uptake was not observed. During
monotonous heating of the sample, active absorption of
hydrogen by the sample began after reaching a
temperature of 300 °C (Fig. 8). The active phase of
hydrogen absorption continued to a temperature of
about 400 °C. At a sample temperature above 450 °C,
the absorption practically ceased. In the temperature
range 300400 °C, the sample absorbed about 0.95%
by weight of hydrogen. Hydrogen evolution during
thermal desorption from this sample occurred in the
range 350600 °С with max at 450 °С, which
significantly differs from the kinetics of desorption of a
hydrogen-saturated small particle at room temperature.
a
b
Fig. 7. Dependences of the temperature of the sample
and heater (a), the pressure in the reaction chamber (b)
on time upon re-saturation of the Ti30Zr45Ni25 sample
with hydrogen at room temperature
To confirm the obtained data, duplicate experiments
on hydrogen sorption-desorption were carried out with a
204 ISSN 1562-6016. ВАНТ. 2020. №1(125)
Ti30Zr45Ni25 sample in a setup with an MX7203 mass
spectrometer. The sample was studied in the air for
7 days after grinding. Absorption at room temperature
was not observed upon exposure to hydrogen for more
than 2 h. Hydrogen sorption began only when heated
above 200 °C. Active absorption took place in the range
of 250350 °C, plots of hydrogen sorption and thermal
desorption after saturation of the samples with hydrogen
are shown in Fig. 8.
a
0
10
20
30
40
50
60
70
80
90
100
110
120
0100 200 300 400 500 600 700 800
Temperature, °С
Pressure, mm.Hg.
b
Fig. 8. Dependence of the pressure in the reaction
chamber on the temperature of the Ti30Zr45Ni25 sample
(7 days in the air) for: sorption (a) and thermal
desorption (b) of hydrogen
Thus, it can be argued that the presence of the
ground Ti30Zr45Ni25 sample in air leads to a gradual
increase in the incubation period before the absorption
of hydrogen at room temperature and subsequently
completely eliminates this process. Nevertheless, the
detected temperature ranges of sorption-desorption and
the corresponding sorption capacity are unique for the
Ti-Zr-Ni system and most other known metal hydride
systems. This material can be an extremely promising
hydrogen accumulator, research is ongoing.
CONCLUSION
The Ti30Zr45Ni25 intermetallic material was
synthesized using the hydride cycle technology with
dehydrogenation of a portion of the (TiH2)30Zr45Ni25
sample by an electron beam in vacuum. The
establishment of a stationary process of gradient heating
of a sample by an electron beam made it possible to
form a layered structure in the sample and fix all stages
of transformations, from the initial hydrides to the
formation of a ternary alloy. Using scanning electron
microscopy and X-ray diffraction analysis, it was
established that under the influence of an electron beam,
structural transformations occur in the sample,
associated with the decay of titanium hydride and
accompanied by a redistribution of hydrogen between
the components of the sample. As a result of synthesis,
the growth structures characteristic of the given system
are formed in the sample, which are a mixture of
(Ti,Zr)2Ni phases, Laves phases C14 L-TiZrNi,
α-(Ti,Zr). The study of hydrogen sorption and
desorption processes by a synthesized sample showed
that the structure of the sample formed upon heating by
an electron beam promotes reversible absorption of
hydrogen at room temperature up to 1.41 wt.% with
heat evolution. Subsequent thermal desorption of
hydrogen begins when the sample is heated above 40 °C.
It was also found that after grinding a sample of
Ti30Zr45Ni25 and being in a ground state for more than
7 days in the air, the material loses its ability to absorb
hydrogen at room temperature.
ACKNOWLEDGEMENTS
Authors thank gratefully to R. Vasilenko for the
sample SEM/EDX investigations and I.V. Kolodiy for
XRD investigations. Also, special thanks to
M.M. Pylypenko and O.M. Bovda for the help in
discussing the results.
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Статья поступила в редакцию 27.11.2019 г.
СИНТЕЗ МАТЕРИАЛОВ НАКОПИТЕЛЕЙ ВОДОРОДА В СИСТЕМЕ Ti-Zr-Ni
ПО ТЕХНОЛОГИИ ГИДРИДНОГО ЦИКЛА ПРИ ДЕГИДРИРОВАНИИ ЭЛЕКТРОННЫМ
ПУЧКОМ В ВАКУУМЕ
А.Е. Дмитренко, В.И. Дубинко, В.Н. Борисенко, К. Ирвин
Проведен синтез интерметаллического материала посредством дегидрирующего отжига образца
(TiH2)30Zr45Ni25 в вакууме электронным пучком. Методом сканирующей электронной микроскопии и
рентгеноструктурного анализа исследованы свойства полученного материала для установления структурно-
фазового состава. Установлено, что длительное воздействие электронного пучка на образец, содержащий
гидрид титана, приводит к ряду структурных превращений в материале, сопровождающихся
перераспределением водорода из титана в цирконий и завершающихся синтезом тройного сплава с
характерными структурами роста. Исследованы процессы сорбциидесорбции водорода синтезированным
образцом, установлены температурные диапазоны данных процессов и поглотительная способность
полученного материала. Показано, что сформировавшаяся при нагреве электронным пучком структура
образца способствует поглощению водорода при комнатной температуре до 1,41 вес.%.
СИНТЕЗ МАТЕРІАЛІВ НАКОПИЧУВАЧІВ ВОДНЮ В СИСТЕМІ Ti-Zr-Ni
ЗА ТЕХНОЛОГІЄЮ ГІДРИДНОГО ЦИКЛУ ПРИ ДЕГІДРУВАННІ ЕЛЕКТРОННИМ
ПУЧКОМ У ВАКУУМІ
О.Є. Дмитренко, В.І. Дубінко, В.М. Борисенко, К. Ірвін
Проведено синтез інтерметалічного матеріалу за допомогою дегідруючого відпалу зразка (TiH2)30Zr45Ni25
у вакуумі електронним пучком. Методом скануючої електронної мікроскопії і рентгеноструктурного аналізу
досліджені властивості отриманого матеріалу для встановлення структурно-фазового складу. Встановлено,
що тривала дія електронного пучка на зразок, що містить гідрид титану, призводить до ряду структурних
перетворень у матеріалі, що супроводжуються перерозподілом водню з титану в цирконій і завершуються
синтезом потрійного сплаву з характерними структурами зростання. Досліджено процеси сорбціїдесорбції
водню синтезованим зразком, встановлені температурні діапазони даних процесів і поглинальна здатність
отриманого матеріалу. Показано, що сформована при нагріванні електронним пучком структура зразка
сприяє поглинанню водню при кімнатній температурі до 1,41 ваг.%.
... Some modern aviation projects are considering ways of using hydrogen as a fuel, in liquid or gaseous form [25,26]. Therefore, there is a need to develop technologies and materials that either allow significant amounts of hydrogen to be accumulated, or create conditions for rapid, safe and efficient production of hydrogen while air travel is underway. The use of QCs or compounds based on the Laves phase C14 L-Ti-Zr-Ni, capable of reversible absorption of significant amount of hydrogen, offer promising avenues of research for hydrogen energy [27]. ...
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