Mykola Hvozdjuk

Dr. Mykola Hvozdjuk


Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 September 2022 in Materials
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Journal Article
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Maciej DutkiewiczMaciej Dutkiewicz
Maciej Dutkiewicz
OHOksana Hembara
Oksana Hembara
YIYaroslav Ivanytskyi
Yaroslav Ivanytskyi
MHMykola Hvozdjuk
Mykola Hvozdjuk
OCOlha Chepil
Olha Chepil
NHNazar Hembara
Nazar Hembara
In the paper, experimental studies of the hydrogen and pre-strained effect on fracture resistance of steam generator steel 22K were carried out. Special cylindrical samples were loaded up to fracture under a uniaxial tensile test with different pre-strained degrees and hydrogen charged times of the material. Stress-strain curves «Si–ei» were plotted. The true strain «ei» in the local volume was determined using the method of optical-digital image correlation (ODIC). The results showed that the hydrogen influence is practically absent in the elastic area of strain. The fracture energy of steel 22K decreases under the hydrogen influence and pre-strain in all investigated cases. It is shown that during six months of air exposure, with the 0% pre-strained samples release almost all hydrogen. In pre-strained samples, the hydrogen concentration decreased by 1–3% compared to the initial values. This indicates that they have trapped hydrogen that cannot escape on its own. Hydrogen embrittlement (HE) indexes for 0% pre-strained samples at different levels of hydrogen-charging calculated by the strain and energy approaches are equal to each other. There is a difference in the values of the HE index depending on the hydrogen-charge time for pre-strained samples. This indicates that both strain and strength characteristics of the material, which are integrally taken into account in the energy approach, are sensitive to HE.

1 September 2019 in Materials Science
Verified
Journal Article
Closed access
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YIYa. L. Ivanyts’kYi
Ya. L. Ivanyts’kYi
MHMykola Hvozdjuk
Mykola Hvozdjuk
OMOleksandr Maksymenko
Oleksandr Maksymenko
SKSylwester Kłysz
Sylwester Kłysz
EKE. V. Kharchenko
E. V. Kharchenko
RSR. О. Shyshkovs’kYi
R. О. Shyshkovs’kYi

1 November 2018 in Materials Science
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Journal Article
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JCJ.-L. Chen
J.-L. Chen
NHN. О. Hembara
N. О. Hembara
MHMykola Hvozdjuk
Mykola Hvozdjuk

1 May 2015 in Materials Science
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Journal Article
Closed access
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OMOleksandr Maksymenko
Oleksandr Maksymenko
YIYa. L. Ivanyts’kyi
Ya. L. Ivanyts’kyi
MHMykola Hvozdjuk
Mykola Hvozdjuk

1 July 2007 in Materials Science
Verified
Journal Article
Closed access
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LML. I. Muravs’kyi
L. I. Muravs’kyi
MHMykola Hvozdjuk
Mykola Hvozdjuk
TPT. I. Polovynko
T. I. Polovynko

11 December 2010 in Materials Science
Verified
Journal Article
Closed access
PDF file
YIYa. L. Ivanyts’kYi
Ya. L. Ivanyts’kYi
LML. I. Muravs’kYi
L. I. Muravs’kYi
OHOksana Hembara
Oksana Hembara
MHMykola Hvozdjuk
Mykola Hvozdjuk
TPT. I. Polovynko
T. I. Polovynko