Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator
On a linear accelerator samples of alloys of zirconium, molybdenum and stainless steels were irradiated by beams of helium ions with an energy of 0.12…4 MeV. The results of thermal desorption of helium from irradiated samples are reported in the temperature range 20…1500°С. The results of the solu...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2018
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| Цитувати: | Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator / R.А. Anokhin, S.M. Dubniuk, B.V. Zaitsev, К.V. Pavlii, V.M. Reshetnikov, O.S. Shevchenko // Вопросы атомной науки и техники. — 2018. — № 3. — С. 178-182. — Бібліогр.: 12 назв. — англ. |
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Anokhin, R.А. Dubniuk, S.M. Zaitsev, B.V. Pavlii, К.V. Reshetnikov, V.M. Shevchenko, O.S. 2019-02-14T12:07:58Z 2019-02-14T12:07:58Z 2018 Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator / R.А. Anokhin, S.M. Dubniuk, B.V. Zaitsev, К.V. Pavlii, V.M. Reshetnikov, O.S. Shevchenko // Вопросы атомной науки и техники. — 2018. — № 3. — С. 178-182. — Бібліогр.: 12 назв. — англ. 1562-6016 PACS: 29.27.-a https://nasplib.isofts.kiev.ua/handle/123456789/147313 On a linear accelerator samples of alloys of zirconium, molybdenum and stainless steels were irradiated by beams of helium ions with an energy of 0.12…4 MeV. The results of thermal desorption of helium from irradiated samples are reported in the temperature range 20…1500°С. The results of the solution of the nonstationary equation of diffusion are presented with allowance for helium deposition profiles and damageability over the thickness of the sample. The determining factor in the formation of the second peak of thermal desorption is the shift in the maximum of the damage profile relative to the maximum profile of helium deposition in irradiated samples. На лінійному прискорювачі були опромінені зразки сплавів цирконію, молібдену і нержавіючих сталей пучками іонів гелію з енергією 0,12…4 МеВ. Наведено результати термодесорбції гелію з опромінених зразків у діапазоні температур 20…1500°С. Представлені результати рішення нестаціонарного рівняння дифузії з урахуванням профілів залягання гелію і пошкоджуваності по товщині зразка. Визначальним фактором виникнення другого піку термодесорбції є зрушення максимуму профілю пошкоджуваності щодо максимуму профілю залягання гелію в опромінених зразках На линейном ускорителе были облучены образцы сплавов циркония, молибдена и нержавеющих сталей пучками ионов гелия с энергией 0,12…4 МэВ. Приведены результаты термодесорбции гелия из облученных образцов в диапазоне температур 20…1500°С. Представлены результаты решения нестационарного уравнения диффузии с учетом профилей залегания гелия и повреждаемости по толщине образца. Определяющим фактором образования второго пика термодесорбции является сдвиг максимума профиля повреждаемости относительно максимума профиля залегания гелия в облученных образцах. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Применение ускорителей в радиационных технологиях Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator Термодесорбція з конструкційних матеріалів, опромінених іонами гелію на лінійному прискорювачі Термодесорбция из конструкционных материалов, облученных ионами гелия на линейном ускорителе Article published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| spellingShingle |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator Anokhin, R.А. Dubniuk, S.M. Zaitsev, B.V. Pavlii, К.V. Reshetnikov, V.M. Shevchenko, O.S. Применение ускорителей в радиационных технологиях |
| title_short |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| title_full |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| title_fullStr |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| title_full_unstemmed |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| title_sort |
тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator |
| author |
Anokhin, R.А. Dubniuk, S.M. Zaitsev, B.V. Pavlii, К.V. Reshetnikov, V.M. Shevchenko, O.S. |
| author_facet |
Anokhin, R.А. Dubniuk, S.M. Zaitsev, B.V. Pavlii, К.V. Reshetnikov, V.M. Shevchenko, O.S. |
| topic |
Применение ускорителей в радиационных технологиях |
| topic_facet |
Применение ускорителей в радиационных технологиях |
| publishDate |
2018 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Термодесорбція з конструкційних матеріалів, опромінених іонами гелію на лінійному прискорювачі Термодесорбция из конструкционных материалов, облученных ионами гелия на линейном ускорителе |
| description |
On a linear accelerator samples of alloys of zirconium, molybdenum and stainless steels were irradiated by
beams of helium ions with an energy of 0.12…4 MeV. The results of thermal desorption of helium from irradiated
samples are reported in the temperature range 20…1500°С. The results of the solution of the nonstationary equation
of diffusion are presented with allowance for helium deposition profiles and damageability over the thickness of the
sample. The determining factor in the formation of the second peak of thermal desorption is the shift in the maximum of the damage profile relative to the maximum profile of helium deposition in irradiated samples.
На лінійному прискорювачі були опромінені зразки сплавів цирконію, молібдену і нержавіючих сталей
пучками іонів гелію з енергією 0,12…4 МеВ. Наведено результати термодесорбції гелію з опромінених зразків у діапазоні температур 20…1500°С. Представлені результати рішення нестаціонарного рівняння дифузії
з урахуванням профілів залягання гелію і пошкоджуваності по товщині зразка. Визначальним фактором виникнення другого піку термодесорбції є зрушення максимуму профілю пошкоджуваності щодо максимуму
профілю залягання гелію в опромінених зразках
На линейном ускорителе были облучены образцы сплавов циркония, молибдена и нержавеющих сталей
пучками ионов гелия с энергией 0,12…4 МэВ. Приведены результаты термодесорбции гелия из облученных
образцов в диапазоне температур 20…1500°С. Представлены результаты решения нестационарного уравнения диффузии с учетом профилей залегания гелия и повреждаемости по толщине образца. Определяющим
фактором образования второго пика термодесорбции является сдвиг максимума профиля повреждаемости
относительно максимума профиля залегания гелия в облученных образцах.
|
| issn |
1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/147313 |
| citation_txt |
Тhermodesorbtion from construction materials irradiated by ions of helium on a linear accelerator / R.А. Anokhin, S.M. Dubniuk, B.V. Zaitsev, К.V. Pavlii, V.M. Reshetnikov, O.S. Shevchenko // Вопросы атомной науки и техники. — 2018. — № 3. — С. 178-182. — Бібліогр.: 12 назв. — англ. |
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| fulltext |
ISSN 1562-6016. ВАНТ. 2018. №3(115) 178
THERMODESORBTION FROM CONSTRUCTION MATERIALS
IRRADIATED BY IONS OF HELIUM ON A LINEAR ACCELERATOR
R.А. Anokhin, S.M. Dubniuk, B.V. Zaitsev, К.V. Pavlii, V.M. Reshetnikov, O.S. Shevchenko
National Science Center “Kharkov Institute of Physics and Technology”, Kharkov, Ukraine
E-mail: sergdubnyuk@ukr.net
On a linear accelerator samples of alloys of zirconium, molybdenum and stainless steels were irradiated by
beams of helium ions with an energy of 0.12…4 MeV. The results of thermal desorption of helium from irradiated
samples are reported in the temperature range 20…1500С. The results of the solution of the nonstationary equation
of diffusion are presented with allowance for helium deposition profiles and damageability over the thickness of the
sample. The determining factor in the formation of the second peak of thermal desorption is the shift in the maxi-
mum of the damage profile relative to the maximum profile of helium deposition in irradiated samples.
PACS: 29.27.-a
INTRODUCTION
Structural materials of nuclear power plants operate
under difficult conditions of neutron irradiation, which
accelerates creep processes, reduces strength and reduc-
es deformation capacity at moderate (20...450°C), high
(500...800°C) and ultrahigh (above 800°C) temperatures
[1]. As a result of nuclear reactions, gaseous impurities
(helium, hydrogen) are formed in the materials, promot-
ing the appearance of helium embrittlement, hydrogen
embrittlement and gas swelling. In thermonuclear reac-
tors, the sources of helium are the products of the ther-
monuclear reaction (d, t), the decay of tritium, the
breeding reaction:
6
Li +
1
n =
3
T +
4
He;
7
Li +
1
n =
3
T +
4
He +
1
n.
In the volume of the material, the greatest contribu-
tion to the production of helium is due to the (n, a) reac-
tion under the action of high-energy neutrons:
A
MZ +
1
n0
f
=
A-3
M'Z-2 +
4
He2 or
A
MZ +
1
n0
f
=
A-4
M'Z-2 +
4
He2.
The source of helium in nuclear reactors are nuclear
reactions in materials under the action of thermal neu-
trons. Comparison of helium production in fusion and
fission reactors shows that the He/dpa ratio in nuclear
reactors is about 30 to 80 times lower compared to fu-
sion reactors [1]. The accumulation of helium in the
structural materials of nuclear and thermonuclear reac-
tors leads to a change in the physicochemical properties
of the materials under irradiation [2 - 5], which indicates
an increase in the negative role of helium when it is
introduced into materials [6, 7]. The ratio between the
rate of helium accumulation and the rate of defect for-
mation (He/dpa) [8, 9], is a key parameter for many
observed phenomena. The development of nuclear pow-
er generates a problem in the development of new radia-
tion-resistant materials for new and future nuclear reac-
tors with a view to ensuring the safety and economy of
electricity produced.
The aim of the work is to irradiate the structural ma-
terials of nuclear and thermonuclear reactors on a linear
accelerator of helium ions with energies of
0.12…4 MeV, followed by a study of the thermal de-
sorption process in the temperature range 20…1500°C,
as well as a mathematical description of the radiation
component of the helium diffusion process taking into
account the profiles of damage and deposition.
1. ACCELERATOR AND INJECTOR
OF HELIUM IONS
At present, most studies of the effect of helium on
the development of radiation damage have been carried
out using ion implantation. To study the processes asso-
ciated with implantation, a linear accelerator of helium
ions with energy of up to 4 MeV operates at the NSC
KIPT [10].
The accelerating section is designed to accelerate Не
+
ions to 4 MeV (input energy is 30 keV/nucl.). In the ac-
celerating structure of the counter-pin type, a method of
variable-phase focusing with a step change in the syn-
chronous phase along the focusing periods is used to fo-
cus the beam [11]. The effectiveness of this method de-
pends on the configuration of the focusing period. The
choice of synchronous phases ensured the capture of a
beam of high-intensity ions in a phase angle of 120°, as
well as the radial and phase stability of ion clusters
along the accelerating structure. In order to ensure the
maximum capture of particles (120°) in the regime of
stable radial and longitudinal motion, the accelerating
field in the initial part of the structure was made incre-
mental. As a result of the calculations and experimental
work performed during the setup and start-up of the
accelerator section, a predetermined distribution of the
electric field in the structure at the operating frequency
of 47.2 MHz was obtained. The main parameters of the
accelerator structure are given in Table 1.
Table 1
Options POS-4
Ion energy at the entrance, keV/nucl. 30
Energy of the accelerated ions, keV/nucl. 975
The ratio of the ion mass-to-charge 4
Operating frequency, MHz 47.2
Maximum accelerating field, kV/cm 85
Overall acceleration rate MeV/m 1.6
Resonator length, m 2.39
Cavity diameter, cm 107.5
Number of drift tubes 32
Pulse current of accelerated ions, mA 6
Input surge current, mA 30
To inject the beam into the accelerator section, an
injector of singly charged helium ions was developed
and fabricated. The injector consists of an ion source, a
beam pulling and focusing system, and an accelerating
tube. To form a beam with given parameters, a source of
mailto:sergdubnyuk@ukr.net
ISSN 1562-6016. ВАНТ. 2018. №3(115) 179
the duoplasmotron type was chosen, with electrons os-
cillating in the anode region. The injector makes it pos-
sible to obtain a beam of singly charged helium ions
with currents of several tens of milliamperes. The main
parameters of the injector are given in Table 2.
Table 2
Injector parameters
The working gas helium
Arc current, A 2…4
The beam current at the output, mA to 20
The energy of the particles at the outlet
of up to, keV
to 140
The beam diameter at the output, mm ~ 8
Working gas pressure in the anode
region of the source, mm Hg
5∙10
-3
Sampling frequency, Hz 2…10
Pulse duration modulator arc, µs 500
The magnetic field source, Oe 300…700
2. IRRADIATION, CHARACTERISTICS OF
SAMPLES AND EXPERIMENTAL RESULTS
To irradiate samples from structural materials, a
camera was developed and fabricated [13]. During the
irradiation, the temperature of the sample, the beam
current, and the irradiation dose were measured. The
design of the chamber allows to change the temperature
of the sample to 1000С, allows to control the vacuum,
which is carried out with the help of vacuum pumps and
turbomolecular pumps up to 4·10
-6
atm. The temperature
of the sample upon irradiation was measured by a
chromel-alumel thermocouple attached to the sample
from the opposite side with respect to the incident beam.
The signal from the thermocouple was amplified by a
differential amplifier. The calibration was carried out
taking into account the length (~ 30 m) of the measuring
wires. The current of the helium ion beam was meas-
ured by a transit sensor installed up to the sample at a
distance of ~ 30 cm and graduated with the help of a
Faraday cylinder installed at the exit of the accelerator,
before each irradiation. The diameter of the beam of
ions incident on the sample is ~ 30 mm, therefore, the
area of the irradiated sample is ≈ 10 cm
2
.
Table 3
Materials and parameters of irradiation
№ Material
Thickn-
ess of
sample,
µA
Energy of
ions Не,
MeV
Average
Irradiation
Tempera-
ture, C
Total
radiation
dose
1 Stainless
steel
200
4
72
7.5∙10
15
2 Steel-3 100 78 1.5∙10
16
3 Zr+2.5%
Nb
250
70
2.3∙10
16
4 Zr 300 58 5∙10
16
5
Zr+1%Nb 250
2.6
40…80
5∙10
16
6 (4+0.12) 5∙10
16
+
5∙10
16
7 0.12 5∙10
16
8 0.12 5∙10
17
9 Nb 16
4 40 5∙10
16
10 Nb+1%Zr 22
During the experiments on the accelerator, irradia-
tion of samples from structural materials was carried
out, the main characteristics of which are presented in
Table 3.
When measuring the main radiation parameters, the
analog-digital converter ZET 210 "Sigma USB" con-
nected to a personal computer was used. This converter
allows you to connect and process signal sources with
different frequency ranges and perform a comparative
analysis. Schemes of devices for measuring the tem-
perature of irradiation, beam current, dose and electro-
physical properties have been created.
In Fig. 1 shows the dependence of the sample tem-
perature on the irradiation time. Similar dependences
were obtained for the peak beam current and the irradia-
tion dose versus time.
0 5 10 15 20 25 30 35 40 45 50
69
70
71
72
73
74
75
76
t, min
T
, 0 C
Turned on
Turned off
Fig. 1. Dependence of the sample temperature
(stainless steel) on the time of irradiation
For all the irradiated samples, using the SRIM pro-
gram, calculations were made of the distributions of dam-
age and helium abundance in thickness. For example, in
Fig. 2 shows the dependences for Zr + 1% Nb, with dos-
es at 120 KeV and 4 MeV identical 5·10
16
ions.
When these curves are approximated by Gaussian de-
pendences, it follows that the dispersion decreases prac-
tically exponentially with decreasing ion energy. The
damage profiles were also calculated in all irradiated
samples and approximate expressions were obtained.
0,0 0,5 1,0 8,5 9,0 9,5 10,0 10,5 11,0
0,0
0,2
0,4
0,6
0,8
1,0
Ф = 5*10
16
Е = 4 MeV
C
on
ce
nt
ra
ti
on
, r
el
at
iv
e
un
it
s
L,µA
Ф = 5*10
16
Е = 120 keV
Fig. 2. The calculated profile of the distribution
of helium ions implanted in Zr + 1% Nb with an energy
of 120 KeV (left graph) and 4 MeV (the first graph),
the dose is 510
15
He/cm
2
The behavior of helium in the materials studied after
irradiating them with helium ions with an energy of
0.12...4 MeV was studied using the thermally stimulated
desorption (TD) technique. In experiments, a thermode-
sorption technique was used in a dynamic mode, in
which the gas pressure in the chamber was proportional
ISSN 1562-6016. ВАНТ. 2018. №3(115) 180
to the rate of desorption from the metal. Samples were
studied in the temperature range 0...1500°C. Studies of
dermodiffusion were carried out [12] at the Institute of
Solid State Physics, Materials Science and Technology
NSC KIPT. The spectra of thermal desorption of helium
from a sample of Zr+1% Nb are given in Fig. 3. More
fully experimental results are presented in [13].
Fig. 3. Thermal desorption spectrum of helium from
a sample of the Zr + 1% Nb alloy irradiated with He
+
ions with energy 4 MeV + 120 keV (upper curve)
and 120 keV (lower curve)
It can be seen from the results that appreciable gas
evolution begins at T ≈ 500°C and extends to
T ≈ 1500°C. In this temperature range, the TD spectrum
is characterized by a superposition of several desorption
peaks. The complexity of the structure of the spectrum
increases with increasing radiation dose. The maximum
gassing is observed in the peak with the maximum tem-
perature near T ≈ 1280C. Moreover, it should be noted
that this stage of desorption is observed both in the spec-
tra of samples irradiated to a dose of Ф = 5·10
15
cm
-2
and
in samples irradiated to a dose 10 times higher. A study
of the gas evolution of helium from samples after their
successive irradiation showed that the structure of the
spectra in this case is less complicated than the spectra
obtained by irradiating this alloy with 120 keV and
2.42 MeV He
+
ions. Noticeable desorption begins at
T ≈ 600°С, the peak of gas evolution with a maximum
at Т ≈ 1200°С predominates in the spectrum.
3. DESCRIPTION OF HELIUM DIFFUSION
FROM IRRADIATED SAMPLES
From an analysis of the experimental data, it follows
that the presence of several peaks in the TD spectra in-
dicates the existence of several discrete stages of helium
separation, distinguished by the mechanisms of helium
escape from the metal. Upon irradiation, helium atoms
interact with crystal lattice defects, which are traps for
helium. In this case, helium is captured by single vacan-
cies, divacancies, clusters of vacancies. And also helium
is captured by dislocations and grain boundaries, inter-
phase boundaries, formation of helium and helium-
vacancy clusters [1]. Traps for their ability to absorb
and release diffusion-bearing atoms are conventionally
divided into three groups: with negligible retention ca-
pacity; traps, which are constant for all temperatures
and times of the experiment, capable of absorbing and
releasing diffusing atoms; traps which, at the tempera-
ture of the experiment, firmly hold the diffusing atoms.
In addition, the effective diffusion coefficient has a
temperature dependence including the activation energy,
which is the sum of the activation energies for simple
interstitial diffusion and the contribution from the bind-
ing energy in the trap. On the diffusing substance, in our
case helium, the external force acts in the process of
diffusion. Then, a flux caused by the action of an exter-
nal force field will be superimposed on the flow of mat-
ter JD, vJ Cv ( v the directed velocity of the sub-
stance acquired under the influence of the field), and the
total flux of the diffusant can be written as follows:
( )J D C x Cv .
In our case, it is necessary to determine the role of
the radiation component, expressed as a function of
damage from the thickness of the sample, and the pro-
file of helium deposition implanted in the sample. In
describing diffusion processes, the role of defects in
materials can be taken into account in two ways: by
modifying differential equations or by modifying the
diffusion coefficient itself, leaving the differential equa-
tion in its original form. You can also use a combination
of these approaches. To describe the diffusion of helium
from irradiated structural materials, we used the equa-
tion in the form:
2
C C
D C V
eff 2
t xx
, (1)
with the following boundary conditions:
C h , tС 0, t max
0, 0,
x x
(2)
where hmax is the maximum range of helium ions in the
sample under irradiation; C is the concentration, t is
the time; x is the coordinate (the diffusion thickness of
the sample); V is the diffusion rate determined by the
following expression:
V D ln C
eff
x
, (3)
where Deff is the effective diffusion coefficient, which
was determined from the experimental data. In Fig. 4
shows the dependence of the effective diffusion coeffi-
cient of helium on the temperature for Zr+1% Nb. It
follows from the dependence that a phase transition of
the irradiated material Zr+1% Nb is observed in the
temperature range 660…800С. The same conclusion
follows from Fig. 5.
Fig. 4. Dependence of the diffusion coefficient
on the temperature for Zr + 1% Nb
ISSN 1562-6016. ВАНТ. 2018. №3(115) 181
This is the experimental temperature dependence of
the heated sample from the time, obtained with a linear
change in the heating power. From Fig. 5 that the slope
of the curve decreases in the range of 660…800С,
which also confirms the presence of a phase transition.
0 100 200 300 400 500
2
5
1 2
см
D 10
сек
a
2
T
,
0
C
t, s
a
1
660
0
C
800
0
C
2
7
1 2
см
D 10
сек
1400
800
660
0
Fig. 5. Experimental dependence of the sample heating
temperature on time (sample Zr + 1% Nb)
These changes must be taken into account in equa-
tion (1) in determining the effective diffusion co-
efficient in the following form:
Const T 660 C,
1
D D T, 660 C T 800 C,
0eff
Const T 800 C,
2
,
,
(4)
where is the proportionality coefficient. In the first
approximation, linear dependence can be used. This
dependence should be taken into account only in the
presence of phase transitions.
The initial conditions for equation (1) were obtained
by approximating the profile of the distribution of heli-
um for Zr+1% Nb and have the form:
2
2907.17 exp 6.67 x 10.68 x 10.68
C x, t 0 Cm 2
2907.17 exp 24.58 x 10.68 x 10.68,
where Cm was normalized to the total radiation dose:
hmax
t C(x, t 0) dx Cm
0
.
The account of the damageability of the sample, af-
ter its irradiation on the accelerator, was taken into ac-
count in the diffusion coefficient as follows. The diffu-
sion coefficient can be represented:
DPA
D D0 i
DPA(x)
,
where DPA the average number of displacements at
the diffusion length, DPA(x) the function of the dis-
tribution of the damage profile, which for Zr+1% Nb is
written:
2
m
2
0.012
, x 10.56
x 10.56 0.1028DPA x DPA
0.1941exp 13.16 x 10.56 , x 10.56.
The average number of offsets is determined by:
hmax1
DPA DPA(x) dx
0hmax
and is normalized to the radiation dose, taking into ac-
count the energy required for a single bias (K the
number of displacements per ion):
hmax
K t DPA(x) dx DPAm
0
.
Then the effective diffusion coefficient can be repre-
sented in the form:
E
i
D D exp0eff
kT(t)
,
where
iE is the activation energy; T is the tempera-
ture that is changed during the experiment; k is the
Boltzmann constant. Numerically solving the diffusion
equation, taking into account the distribution functions
of helium and damage and taking into account the ex-
perimental parameters, namely, the temperature change
from time to time, the calculated thermodesorption
curves of helium from irradiated samples were obtained.
In Fig. 6 shows the calculated and experimental de-
pendences of helium desorption from a Zr+1% Nb sam-
ple irradiated by helium ions with an energy of 4 MeV
on a linear accelerator.
Fig. 6. Calculated (upper curve) and experimental
(lower curve) desorption curves from a Zr + 1% Nb
sample irradiated with helium ions with an energy
of 4 MeV
It follows from the calculations that the maximum of
the damage profile is shifted to the surface of the sample
on which the beam was incident, in relation to the max-
imum profile of helium deposition. In this case, the
problem can be interpreted as the motion of helium in
the field of radiation damage. This effect explains the
appearance of a second peak on the desorption curve.
CONCLUSIONS
On a linear accelerator of helium ions with energies
0.12…4 MeV, irradiation of structural materials was
carried out with subsequent study of thermal desorption.
In the description it was shown that the second peak on
the desorption graph is formed due to the shift of the
maximum of the radiation damage relative to the maxi-
mum of helium deposition.
ISSN 1562-6016. ВАНТ. 2018. №3(115) 182
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Article received 09.10.2017
ТЕРМОДЕСОРБЦИЯ ИЗ КОНСТРУКЦИОННЫХ МАТЕРИАЛОВ,
ОБЛУЧЕННЫХ ИОНАМИ ГЕЛИЯ НА ЛИНЕЙНОМ УСКОРИТЕЛЕ
Р.А. Анохин, С.Н. Дубнюк, Б.В. Зайцев, К.В. Павлий, В.Н. Решетников, А.С. Шевченко
На линейном ускорителе были облучены образцы сплавов циркония, молибдена и нержавеющих сталей
пучками ионов гелия с энергией 0,12…4 МэВ. Приведены результаты термодесорбции гелия из облученных
образцов в диапазоне температур 20…1500С. Представлены результаты решения нестационарного уравне-
ния диффузии с учетом профилей залегания гелия и повреждаемости по толщине образца. Определяющим
фактором образования второго пика термодесорбции является сдвиг максимума профиля повреждаемости
относительно максимума профиля залегания гелия в облученных образцах.
ТЕРМОДЕСОРБЦІЯ З КОНСТРУКЦІЙНИХ МАТЕРІАЛІВ,
ОПРОМІНЕНИХ ІОНАМИ ГЕЛІЮ НА ЛІНІЙНОМУ ПРИСКОРЮВАЧІ
Р.А. Анохін, С.М. Дубнюк, Б.В. Зайцев, К.В. Павлій, В.М. Решетніков, О.С. Шевченко
На лінійному прискорювачі були опромінені зразки сплавів цирконію, молібдену і нержавіючих сталей
пучками іонів гелію з енергією 0,12…4 МеВ. Наведено результати термодесорбції гелію з опромінених зраз-
ків у діапазоні температур 20…1500С. Представлені результати рішення нестаціонарного рівняння дифузії
з урахуванням профілів залягання гелію і пошкоджуваності по товщині зразка. Визначальним фактором ви-
никнення другого піку термодесорбції є зрушення максимуму профілю пошкоджуваності щодо максимуму
профілю залягання гелію в опромінених зразках.
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