Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades
The reliability of the vane apparatus of steam turbines largely determines the operation of the turbine as a whole. The results of scientific research indicate that the surface operation of the blades in the wet-steam flow is caused by a combination of corrosion and drip erosion. The presence of che...
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Hlushkova, D.B. Bahrov, V.A. Hrinchenko, O.D. Hnatiuk, A.A. Kalinina, N.E. Kalinin, V.T. 2023-12-01T19:08:27Z 2023-12-01T19:08:27Z 2021 Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades / D.B. Hlushkova, V.A. Bahrov, O.D. Hrinchenko, A.A. Hnatiuk, N.E. Kalinina, V.T. Kalinin // Problems of Atomic Science and Technology. — 2021. — № 2. — С. 136-141. — Бібліогр.: 7 назв. — англ. 1562-6016 DOI: https://doi.org/10.46813/2021-132-136 https://nasplib.isofts.kiev.ua/handle/123456789/194963 621.785 The reliability of the vane apparatus of steam turbines largely determines the operation of the turbine as a whole. The results of scientific research indicate that the surface operation of the blades in the wet-steam flow is caused by a combination of corrosion and drip erosion. The presence of chemical elements and compounds in the working fluid intensifies the process of blade wear. The pH value of the working environment, which can fluctuate significantly during operation, has a significant effect on the wear characteristics. The influence of methods of strengthening the leading edges of steam turbine blades made of steel is analyzed 15H11MF on corrosion resistance. Corrosion tests of blade samples were carried out, the inlet edges of which were strengthened in three ways: high current amplification, electrospark alloying with T15K6 alloy, electrospark alloying with steel 15H11MF. According to the results of the tests, the layer strengthened by hardening by high-frequency currents has the lowest corrosion rate, the layer strengthened by electrospark alloying with T15K6 hard alloy has the highest. The corrosion rate of the layer reinforced by electrospark alloying of steel 15H11MF is 2.1 less than that of the layer reinforced with T15K6 alloy. Надійність роботи лопаткового апарата парових турбін у значній мірі визначає роботу турбіни в цілому. Результати наукових досліджень свідчать про те, що поверхневе спрацювання робочих лопаток у вологопаровому потоці викликається поєднанням корозії і каплеударної ерозії. Наявність у робочому тілі хімічних елементів і сполук інтенсифікують процес зносу лопаток. Відчутний вплив на характеристики зносу надає значення рН робочого середовища, яке може значно коливатися в процесі експлуатації. Проаналізовано вплив способів зміцнення вхідних крайок лопаток парових турбін зі сталі 15Х11МФ на корозійну стійкість. Проведено корозійні випробування зразків лопаток, вхідні крайки яких зміцнені трьома способами: струмами високої частоти, електроіскровим легуванням сплавом Т15К6, електроіскровим легуванням сталлю 15Х11МФ. За результатами проведених випробувань найменшу швидкість корозії має шар, зміцнений загартуванням струмами високої частоти, найбільшу - шар, зміцнений електроіскровим легуванням твердим сплавом Т15К6. Швидкість корозії шару, зміцненого електроіскровим легуванням сталлю 15Х11МФ, у 2,1 рази менше, ніж у шару, зміцненого сплавом Т15К6. Надежность работы лопаточного аппарата паровых турбин в значительной степени определяет работу турбины в целом. Результаты научных исследований свидетельствуют о том, что поверхностный износ рабочих лопаток во влажно-паровом потоке вызывается сочетанием коррозии и каплеударной эрозии. Наличие в рабочем теле химических элементов и соединений интенсифицируют процесс износа лопаток. Ощутимое влияние на характеристики износа имеет значение рН рабочей среды, которое может значительно колебаться в процессе эксплуатации. Проанализировано влияние способов упрочнения входных кромок лопаток паровых турбин из стали 15Х11МФ на коррозионную стойкость. Проведены коррозионные испытания образцов лопаток, входные кромки которых упрочнены тремя способами: токами высокой частоты, электроискровым легированием сплавом Т15К6, электроискровым легированием сталью 15Х11МФ-Ш. По результатам проведенных испытаний наименьшую скорость коррозии имеет слой, упрочненный закалкой токами высокой частоты, наибольшую - слой, упрочненный электроискровым легированием твердым сплавом Т15К6. Скорость коррозии слоя, упрочненного электроискровым легированием сталью 15Х11МФ, в 2,1 раза меньше, чем у слоя, укрепленного сплавом Т15К6. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Physics of radiation and ion-plasma technologies Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades Корозійна стійкість зміцнених шарів лопаток парових турбін зі сталі 15Х11МФ Коррозионная стойкость упрочненных слоев лопаток паровых турбин из стали 15Х11МФ Article published earlier |
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Digital Library of Periodicals of National Academy of Sciences of Ukraine |
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| title |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades |
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Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades Hlushkova, D.B. Bahrov, V.A. Hrinchenko, O.D. Hnatiuk, A.A. Kalinina, N.E. Kalinin, V.T. Physics of radiation and ion-plasma technologies |
| title_short |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades |
| title_full |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades |
| title_fullStr |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades |
| title_full_unstemmed |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades |
| title_sort |
corrosion resistance of reinforced layers of 15х11mf steel steam turbine blades |
| author |
Hlushkova, D.B. Bahrov, V.A. Hrinchenko, O.D. Hnatiuk, A.A. Kalinina, N.E. Kalinin, V.T. |
| author_facet |
Hlushkova, D.B. Bahrov, V.A. Hrinchenko, O.D. Hnatiuk, A.A. Kalinina, N.E. Kalinin, V.T. |
| topic |
Physics of radiation and ion-plasma technologies |
| topic_facet |
Physics of radiation and ion-plasma technologies |
| publishDate |
2021 |
| language |
English |
| container_title |
Вопросы атомной науки и техники |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| format |
Article |
| title_alt |
Корозійна стійкість зміцнених шарів лопаток парових турбін зі сталі 15Х11МФ Коррозионная стойкость упрочненных слоев лопаток паровых турбин из стали 15Х11МФ |
| description |
The reliability of the vane apparatus of steam turbines largely determines the operation of the turbine as a whole. The results of scientific research indicate that the surface operation of the blades in the wet-steam flow is caused by a combination of corrosion and drip erosion. The presence of chemical elements and compounds in the working fluid intensifies the process of blade wear. The pH value of the working environment, which can fluctuate significantly during operation, has a significant effect on the wear characteristics. The influence of methods of strengthening the leading edges of steam turbine blades made of steel is analyzed 15H11MF on corrosion resistance. Corrosion tests of blade samples were carried out, the inlet edges of which were strengthened in three ways: high current amplification, electrospark alloying with T15K6 alloy, electrospark alloying with steel 15H11MF. According to the results of the tests, the layer strengthened by hardening by high-frequency currents has the lowest corrosion rate, the layer strengthened by electrospark alloying with T15K6 hard alloy has the highest. The corrosion rate of the layer reinforced by electrospark alloying of steel 15H11MF is 2.1 less than that of the layer reinforced with T15K6 alloy.
Надійність роботи лопаткового апарата парових турбін у значній мірі визначає роботу турбіни в цілому. Результати наукових досліджень свідчать про те, що поверхневе спрацювання робочих лопаток у вологопаровому потоці викликається поєднанням корозії і каплеударної ерозії. Наявність у робочому тілі хімічних елементів і сполук інтенсифікують процес зносу лопаток. Відчутний вплив на характеристики зносу надає значення рН робочого середовища, яке може значно коливатися в процесі експлуатації. Проаналізовано вплив способів зміцнення вхідних крайок лопаток парових турбін зі сталі 15Х11МФ на корозійну стійкість. Проведено корозійні випробування зразків лопаток, вхідні крайки яких зміцнені трьома способами: струмами високої частоти, електроіскровим легуванням сплавом Т15К6, електроіскровим легуванням сталлю 15Х11МФ. За результатами проведених випробувань найменшу швидкість корозії має шар, зміцнений загартуванням струмами високої частоти, найбільшу - шар, зміцнений електроіскровим легуванням твердим сплавом Т15К6. Швидкість корозії шару, зміцненого електроіскровим легуванням сталлю 15Х11МФ, у 2,1 рази менше, ніж у шару, зміцненого сплавом Т15К6.
Надежность работы лопаточного аппарата паровых турбин в значительной степени определяет работу турбины в целом. Результаты научных исследований свидетельствуют о том, что поверхностный износ рабочих лопаток во влажно-паровом потоке вызывается сочетанием коррозии и каплеударной эрозии. Наличие в рабочем теле химических элементов и соединений интенсифицируют процесс износа лопаток. Ощутимое влияние на характеристики износа имеет значение рН рабочей среды, которое может значительно колебаться в процессе эксплуатации. Проанализировано влияние способов упрочнения входных кромок лопаток паровых турбин из стали 15Х11МФ на коррозионную стойкость. Проведены коррозионные испытания образцов лопаток, входные кромки которых упрочнены тремя способами: токами высокой частоты, электроискровым легированием сплавом Т15К6, электроискровым легированием сталью 15Х11МФ-Ш. По результатам проведенных испытаний наименьшую скорость коррозии имеет слой, упрочненный закалкой токами высокой частоты, наибольшую - слой, упрочненный электроискровым легированием твердым сплавом Т15К6. Скорость коррозии слоя, упрочненного электроискровым легированием сталью 15Х11МФ, в 2,1 раза меньше, чем у слоя, укрепленного сплавом Т15К6.
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1562-6016 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/194963 |
| citation_txt |
Corrosion resistance of reinforced layers of 15Х11MF steel steam turbine blades / D.B. Hlushkova, V.A. Bahrov, O.D. Hrinchenko, A.A. Hnatiuk, N.E. Kalinina, V.T. Kalinin // Problems of Atomic Science and Technology. — 2021. — № 2. — С. 136-141. — Бібліогр.: 7 назв. — англ. |
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136 ISSN 1562-6016. ВАНТ. 2021. №2(132)
https://doi.org/10.46813/2021-132-136
UDC 621.785
CORROSION RESISTANCE OF REINFORCED LAYERS
OF 15Х11МФ STEEL STEAM TURBINE BLADES
D.B. Hlushkova
1
, V.A. Bahrov
1
, O.D. Hrinchenko
1
, A.A. Hnatiuk
1
,
N.E. Kalinina
2
, V.T. Kalinin
3
1
Kharkiv National Automobile and Highway University,
Kharkiv, Ukraine
Е-mail: diana@khadi.kharkov.ua;
2
Oles Honchar Dnipro National University, Dnipro, Ukraine;
3
National Metallurgical Academy of Ukraine, Dnipro, Ukraine
Е-mail: kalinina.dnu@gmail.com
The reliability of the vane apparatus of steam turbines largely determines the operation of the turbine as a whole.
The results of scientific research indicate that the surface operation of the blades in the wet-steam flow is caused by
a combination of corrosion and drip erosion. The presence of chemical elements and compounds in the working
fluid intensifies the process of blade wear. The pH value of the working environment, which can fluctuate
significantly during operation, has a significant effect on the wear characteristics. The influence of methods of
strengthening the leading edges of steam turbine blades made of steel is analyzed 15H11MF on corrosion resistance.
Corrosion tests of blade samples were carried out, the inlet edges of which were strengthened in three ways: high
current amplification, electrospark alloying with T15K6 alloy, electrospark alloying with steel 15H11MF.
According to the results of the tests, the layer strengthened by hardening by high-frequency currents has the lowest
corrosion rate, the layer strengthened by electrospark alloying with T15K6 hard alloy has the highest. The corrosion
rate of the layer reinforced by electrospark alloying of steel 15H11MF is 2.1 less than that of the layer reinforced
with T15K6 alloy.
INTRODUCTION
In the complex of issues that determine the
reliability and efficiency of turbines in thermal and
nuclear power plants, the reliability of the vane
apparatus – the most expensive element of the turbine,
which is most often damaged – is of great importance.
The working conditions require high hardness of the
leading edges, high erosion resistance, no negative
influence of the parameters of forming a protective
coating on mechanical properties, and high corrosion
properties [1].
This problem is especially acute for the working
blades of the last stages low-pressure cylinders, the
corrosion and erosion wear of which determines the
service life of turbines.
Corrosion damage to the blades is observed to
varying degrees on the equipment of all turbine types.
This is due to the fact that the steam environment
always contains corrosive substances, the amount of
which depends on the rate of damage development.
The corrosion damage in the form of pitting and
honeycombs is a stress concentrator. Depending on the
size, number and location, the working blades and disks
are destroyed. With significant metal losses due to
corrosion, the strength characteristics of the blades
decrease and the natural vibration frequencies change.
The formation of such damage during operation usually
occurs on steps located in the phase transition zone and
less often in the wet steam zone. During prolonged
downtime of the turbine, pitting and ulcers can form
along the entire flow part of the turbine (standstill
corrosion), as well as near extractors and drains. This is
due to condensation of steam getting the surface of the
flow part of a non-working turbine through loosely
closed or defective fittings of drains, extractors, etc.
Analysis of the results of surveys of the disks and
turbine blade apparatus metal showed that significant
corrosion damage to the disks and working blades
during operation occurs only at the stages of turbines
operating in the phase transition zone (the wet steam
zone from the state of dry saturated steam to a humidity
of about 6%). Such corrosion damage to the discs and
working blades during the operation of the turbine in the
area of superheated steam was not detected.
The results of scientific studies performed in recent
years [2, 3] indicate that the surface operation of
working blades in a wet steam flow is caused by a
combination of corrosion and water droplet erosion
(Fig. 1).
The presence of chemical elements and compounds
in the working fluid intensifies the process of erosion
wear. A significant influence on the characteristics of
erosion wear makes the pH value of the working
medium, which can vary significantly during operation.
To increase the service life of turbine blades, it is
necessary to establish a mechanism for degradation of
their surface due to corrosion and erosion.
A complex phenomenon, such as the destruction of
the surface of the blade feather as a result of exposure to
aggressive environmental factors, requires experimental
research. One of the ways to reduce the erosion wear of
the working blades is to increase the efficiency of anti-
erosion properties by forming protective layers on the
leading edges that can withstand the influence of
operational factors.
mailto:diana@khadi.kharkov.ua
ISSN 1562-6016. ВАНТ. 2021. №2(132) 137
a b
c d
Fig. 1. Structure of destruction zones of the leading edges of steam turbine blades of the last stages of low
pressure cylinders during operation
Analysis of publications [5–7] showed that the
problem of erosion and corrosion damage to working
blades exposed to a complex range of low-cycle and
high-frequency thermo mechanical loads during
operation is relevant for more than 70 years, but to date
it has been partially solved, so research in the field of
protective layers of blades is an important aspect in
solving this problem.
The purpose of the article is to study the condition of
the surface layer of the working blade of a steam turbine
made of 15H11MF steel, after hardening with high
frequency currents, electric-flash alloying with T15K6
alloy, electric-flash alloying with 15H11MF-SH steel, to
assess the corrosion resistance of the reinforced areas of
the blade feather, to perform a comparative assessment
of the protective layer properties.
MATERIALS AND METHODS
OF RESEARCH
The study was performed on samples from steel
blade blanks 15H11MF-SH, made by stamping. The
chemical composition of steel 15H11MF are shown in
Table 1.
Table 1
Chemical composition of steel
The content of chemical elements, %
C Cr Ni Mo V Si Mn S P
0.12…0.19 10.0…11.5 – 0.6…0.8 0.25…0.4 ≤ 0.5 ≤ 0.7 ≤0.025 ≤0.03
Steel was used for surface hardening by the EIL
method 15H11MF and alloy Т15К6. Alloy Т15К6
consists of two carbides of the titanium-tungsten group,
essentially a composite material (Table 2).
Table 2
Chemical composition of the alloy Т15К6
WC TiC Co
79 15 6
The blades for research are made on JSC
“Turboatom”. To perform the operations of hardening
the surface of the shoulder blades by the method of
hardening with high-frequency currents, installations for
hardening VCHI-63/044 were used. The EIL-8A unit
was used for electrospark alloying. Evaluation of the
properties of materials was performed using the
methods of mechanical, metallographic, X-ray
structural, micro-X-ray diffraction analyzes, electron
microscopy. Bench, laboratory and industrial tests were
performed using methods that meet the State Standards
of Ukraine and ISO standards.
THE RESULTS OF RESEARCH AND THEIR
DISCUSSION
In order to determine the corrosive effect of the
medium, water samples were taken at the nuclear power
plant K 220-44-2 turbine. The acidity value of the
samples and the electrical conductivity of water are
given in Table 3.
In all selected samples, pH > 7, the acidity values
vary from 9.4 to 11.55, which corresponds to the pH
values of an alkaline (basic) solution. The electrical
conductivity varies quite significantly: in samples 1–4
the conductivity varies from 210 to 810 G, in samples
5–9 – from 14.5 to 22.5 G, which indicates the
heterogeneity of water in terms of impurity content. The
anion content in the obtained water samples was also
determined.
138 ISSN 1562-6016. ВАНТ. 2021. №2(132)
Table 3
Results of measuring water acidity (pH) and
electrical conductivity
The measurement results showed an extremely large
number of metal ions, and the presence of Al, Fe, Cr,
Ni, Cu, and Zn. Cr, W was found using the
electromagnetic trap, and the content of them can only
be the result of some corrosion, erosion of the blades,
which is quite logical: the blades are made of 15H11MF
chromium-nickel steel, the leading edges are reinforced
with an T15K6 alloy comprising tungsten carbide.
The presence of metal impurities in water samples
indicates the erosion processes during the operation of
the turbine blade apparatus. Nitrites and nitrates are
present in ion concentrations in very small amounts.
In accordance with the obtained water quality
results, HN3 corrosive medium with an acidity of pH 9.6
was selected during the studies.
The study of samples from blades, the leading edge
of which was reinforced by various methods:
microwave quenching with subsequent tempering
(sample 1), electrospark alloying (ESA) with traditional
T15K6 alloy (sample 2), electrospark alloying with steel
identical to the blade material, 15H11MF-SH
(sample 3). The samples were taken from degree 5
blades made of 15Х11МФ steel (Fig. 2).
a b c
Fig. 2. Type of test samples: a – sample 1; b – sample 2; c – sample 3
The study of the surface condition of the blade
samples in the hardening zone was performed in two
sections marked as “Position 1” and “Position 2”. Part
of the sample marked as “Position 1” was in a vapor
medium, part of the sample marked as “Position 2” was
immersed in an aqueous solution with an acidity of
pH 9.6. The surface condition of the sample before
testing was recorded using a SEM image.
SEM images of microwave reinforced sample 1 are
shown in Fig. 3 at magnifications of ×50 and ×1000
before exposure to a corrosive environment. The surface
condition was studied after exposure for 28 days in an
aggressive environment. This exposure time did not
cause significant damage to the surface of the blade.
a b
Fig. 3. Sample 1 “Position 2”:
a – before the test for exposure to a corrosive environment; b – after the test
When examining the surface of a sample reinforced
by ESD with alloy T15K6, it was found that the surface
is very heterogeneous (Fig. 4), even with irregularities
detected at low-resolution magnifications, there are
holes (craters) on the treated surface. This is due to the
fact that during electrospark alloying, local heating of
the metal occurs and microscopic shrinkage shells are
formed. Such relief is typical for this type of surface
reinforcement. Corrosion destruction occurs locally,
mainly at the interface for the base metal of the blade
(Fig. 5).
Sample
number
pH of water
samples
Electrical conductivity
of water, siemens,
G, S∙sm
–1
1 11.09 580
2 10.34 235
3 11.55 810
4 10.31 210
5 9.4 20.5
6 9.7 14.5
7 9.7 15.0
8 9.81 22.5
9 9.65 17.0
ISSN 1562-6016. ВАНТ. 2021. №2(132) 139
Fig. 4. Sample 2 before testing for exposure to corrosive environment
a b
Fig. 5. SEM image of sample 2 “Position 1” in Location 2:
a – before and b – after the test
The surface of the sample reinforced by ESA with
15H11MF steel is also heterogeneous, as on sample 2,
which is typical for electrospark surface treatment.
Although corrosion affected the entire surface, a
relatively thick layer of corrosion was formed with
significant local differences. In Fig. 6 this is illustrated
in more detail. At the edges of the holes, the
accumulation of a corrosive product is appear: the
deposition of a certain amount of salt, oxide in the holes
and ribs.
а
b
Fig. 6. SEM image of sample 3: a – before and b – after the test
For electrochemical corrosion tests, electrodes with a
geometric surface area of 0.5…1 cm
2
made of a blade
sample were used. The sides without surface treatment
were masked with epoxy adhesive. The measurements
were carried out in a nitrogen-oxygen solution, the
acidity of which was adjusted to pH 9.6 using ammonia
at 25 °C. An oxygen-free ammonia closed system was
heated to 50 °C, and after stabilizing the open circuit
140 ISSN 1562-6016. ВАНТ. 2021. №2(132)
potential, the resistance of the solution between the
working electrode and the comparison electrode (usually
2…5 kΩ) was first determined by measuring the
impedance. Then cathodic and anode polarization was
performed from the open circuit potential in the range of
±250 mV.
Evans diagrams are plotted and the corrosion rate is
determined for each type of reinforcement (Table 4).
Table 4
Comparison of corrosion indicators of samples
Sample
number
Reinforcement
method
Ekorr,
mV
Jkorr,
A∙cm
-2
Βa,
mV
Βk,
mV
Corrosion rate
um per year
1 UHF -255 3.5…10
-8
300 180 0.4
2 T15K6 ESA -602 2.3…10
-6
220 335 12.0
3 15Х11МФ ESA -410 4.9…10
-7
400 220 5.6
CONCLUSIONS
Corrosion tests of blade samples were carried out,
the leading edges of which are reinforced in three ways:
by reinforcing with high-frequency currents,
electrospark alloying with T15K6 alloy, and
electrospark alloying with 15H11MF-SH steel.
The corrosion resistance of the samples was
determined, which showed the hardening of the alloy
Т15К6 by the method of electrospark doping, is the
worst in terms of corrosion resistance.
In fact, the uneven corrosion of samples reinforced
by electrospark alloying is higher compared to samples
reinforced by high-frequency currents. In these samples,
sensitivity to local corrosion was detected, so it is
important to obtain layers with the maximum density of
sections modified by the alloying electrode when
performing the technological operation of electrospark
alloying.
According to the results of the tests, the layer
reinforced by quenching with high-frequency currents
has the lowest rate of corrosion, and the layer reinforced
by electrospark alloying with T15K6 hard alloy has the
highest rate. The corrosion rate of a layer reinforced
with electrospark alloying with 15Х11МФ steel is 2.1
less than that of a layer reinforced with T15K6 alloy.
REFERENCES
1. A.L. Shubenko, A.E. Kovalskii. Dropstroke
erosion of blades devices of steam turbines. Forecast
and methods of safeguard // Bulletin of the National
Technical University “KhPI”: Proceedings Ser.: Power
and Heat Engineering Processes and Equipment.
Kharkiv: NTU “KHPI”, 2012, N 7, p. 76-87.
2. E.K. Sevidova, V.M. Matsevityi, I.B. Kazak,
K.V. Vakulenko. Assessment of protective properties of
multi-layer coatings for steam turbine blades //
Electronic Processing of Materials. 2007, N 6, p. 4-9.
3. O. Bashar. Enhancement of Corrosion Resistance
in Steam Turbines Blades // Nanoparticles Coatings
Al-Nahrain Journal for Engineering Sciences (NJES).
2017, v. 20, N 5, p. 1172-1181.
4. S.S. Vinogradova, R.A. Kaidrikov, B.L. Zhurav-
lev. Calculation of corrosion indicators and parameters
of corrosion systems. Kazan: “KNRTU”, 2013, 176 p.
5. A.D. Mingazhev, A.V. Novikov, N.K. Krioni,
R.R. Bekishev. Protective coating for steam turbine
blades // Oil and Gas Engineering Electronic Scientific
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6. N.E. Kalinina, D.B. Hlushkova, O.D. Hrin-
chenko, T.V. Nosova, A.A. Reznikov. Hardening of
leading edges of turbine blades by electrospark alloing //
Problems of Atomic Science and Technology. 2019,
N 2(120), p. 151-154.
7. D.B. Hlushkova, Y.V. Ryzhkov, L.L. Kostina,
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Статья поступила в редакцию 25.02.2021 г.
КОРРОЗИОННАЯ СТОЙКОСТЬ УПРОЧНЕННЫХ СЛОЕВ ЛОПАТОК ПАРОВЫХ
ТУРБИН ИЗ СТАЛИ 15Х11МФ
Д.Б. Глушкова, В.А. Багров, Е.Д. Гринченко, А.А. Гнатюк, Н.Е. Калинина, В.Т. Калинин
Надежность работы лопаточного аппарата паровых турбин в значительной степени определяет работу
турбины в целом. Результаты научных исследований свидетельствуют о том, что поверхностный износ
рабочих лопаток во влажно-паровом потоке вызывается сочетанием коррозии и каплеударной эрозии.
Наличие в рабочем теле химических элементов и соединений интенсифицируют процесс износа лопаток.
Ощутимое влияние на характеристики износа имеет значение рН рабочей среды, которое может значительно
колебаться в процессе эксплуатации. Проанализировано влияние способов упрочнения входных кромок
лопаток паровых турбин из стали 15Х11МФ на коррозионную стойкость. Проведены коррозионные
испытания образцов лопаток, входные кромки которых упрочнены тремя способами: токами высокой
частоты, электроискровым легированием сплавом Т15К6, электроискровым легированием сталью
15Х11МФ-Ш. По результатам проведенных испытаний наименьшую скорость коррозии имеет слой,
упрочненный закалкой токами высокой частоты, наибольшую слой, упрочненный электроискровым
легированием твердым сплавом Т15К6. Скорость коррозии слоя, упрочненного электроискровым
легированием сталью 15Х11МФ, в 2,1 раза меньше, чем у слоя, укрепленного сплавом Т15К6.
ISSN 1562-6016. ВАНТ. 2021. №2(132) 141
КОРОЗІЙНА СТІЙКІСТЬ ЗМІЦНЕНИХ ШАРІВ ЛОПАТОК ПАРОВИХ ТУРБІН
ЗІ СТАЛІ 15Х11МФ
Д.Б. Глушкова, В.А. Багров, О.Д. Грінченко, А.А. Гнатюк, Н.Є. Калініна, В.Т. Калінін
Надійність роботи лопаткового апарата парових турбін у значній мірі визначає роботу турбіни в цілому.
Результати наукових досліджень свідчать про те, що поверхневе спрацювання робочих лопаток у волого-
паровому потоці викликається поєднанням корозії і каплеударної ерозії. Наявність у робочому тілі хімічних
елементів і сполук інтенсифікують процес зносу лопаток. Відчутний вплив на характеристики зносу надає
значення рН робочого середовища, яке може значно коливатися в процесі експлуатації. Проаналізовано
вплив способів зміцнення вхідних крайок лопаток парових турбін зі сталі 15Х11МФ на корозійну стійкість.
Проведено корозійні випробування зразків лопаток, вхідні крайки яких зміцнені трьома способами:
струмами високої частоти, електроіскровим легуванням сплавом Т15К6, електроіскровим легуванням сталлю
15Х11МФ. За результатами проведених випробувань найменшу швидкість корозії має шар, зміцнений
загартуванням струмами високої частоти, найбільшу шар, зміцнений електроіскровим легуванням твердим
сплавом Т15К6. Швидкість корозії шару, зміцненого електроіскровим легуванням сталлю 15Х11МФ, у
2,1 рази менше, ніж у шару, зміцненого сплавом Т15К6.
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