Integrated analysis of WWER-440 RPV weld re-embrittlement after annealing

Kryukov, A.; Debarberis, L.; Ballesteros, A.; Kršjak, Vladimír; Burcl, Rudolf; Рогожкин, С. В.; Никитин, А. А.; Aleev, A. A.; Залужный, А. Г.; Grafutin, V. I.; Ilyukhina, O. V.; Funtikov, Yu. V.; Zeman, A.

doi:10.1016/j.jnucmat.2012.06.005

Cited by 23 publications

(3 citation statements)

References 26 publications

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“…PAS techniques are proven to be one of the most powerful and well-established tools for detailed characterization of vacancy-type defects in metals and alloys [22][23][24][25]. PAS using variable mono-energy positron beams allows one to probe the depth profile of a surface and near-surface defects in ion-irradiated structural materials [26], and has been successfully applied to study microstructural evolutions in RPV steels [27][28][29][30][31]. In the past 20 years, a growing body of evidence showed that the hydrogen ions implantation can emulate the neutron irradiation-induced microstructural damages, which provides a basis for its use in screening of new structural materials in current and future advanced reactors, while much fewer experiments have been done to benchmark Fe-ion implantation, which are technically more difficult but also worth for consideration at the higher energy treatment.…”

Section: Introductionmentioning

confidence: 99%

Radiation Damage of Reactor Pressure Vessel Steels Studied by Positron Annihilation Spectroscopy—A Review

Slugeň

Sojak

Egger

et al. 2020

Metals

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Safe and long term operation of nuclear reactors is one of the most discussed challenges in nuclear power engineering. The radiation degradation of nuclear design materials limits the operational lifetime of all nuclear installations or at least decreases its safety margin. This paper is a review of experimental PALS/PLEPS studies of different nuclear reactor pressure vessel (RPV) steels investigated over last twenty years in our laboratories. Positron annihilation lifetime spectroscopy (PALS) via its characteristics (lifetimes of positrons and their intensities) provides useful information about type and density of radiation induced defects. The new results obtained on neutron-irradiated and hydrogen ions implanted German steels were compared to those from the previous studies with the aim to evaluate different processes (neutron flux/fluence, thermal treatment or content of selected alloying elements) to the microstructural changes of neutron irradiated RPV steel specimens. The possibility of substitution of neutron treatment (connected to new defects creation) via hydrogen ions implantation was analyzed as well. The same materials exposed to comparable displacement damage (dpa) introduced by neutrons and accelerated hydrogen ions shown that in the results interpretation the effect of hydrogen as a vacancy-stabilizing gas must be considered, too. This approach could contribute to future studies of nuclear fission/fusion design steels treated by high levels of neutron irradiation.

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Section: Introductionmentioning

confidence: 99%

Radiation Damage of Reactor Pressure Vessel Steels Studied by Positron Annihilation Spectroscopy—A Review

Slugeň

Sojak

Egger

et al. 2020

Metals

View full text Add to dashboard Cite

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“…LTO of an NPP may be conditioned by life-limiting processes and features of structures, systems, and components—the emphasis is on the irreplaceable reactor pressure vessel (RPV) and its construction steel. Degradation of its mechanical properties is the crucial limiting factor of NPP lifespan [ 2 ]. Elements causing degradation of RPV properties are neutron irradiation, high temperature and pressure, fatigue, corrosion, etc.…”

Section: Introductionmentioning

confidence: 99%

Positron Annihilation Study of RPV Steels Radiation Loaded by Hydrogen Ion Implantation

et al. 2022

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Specimens of 15Kh2MFAA steel used for reactor pressure vessels V-213 (VVER-440 reactor) were studied by positron annihilation techniques in terms of their radiation resistance and structural recovery after thermal treatment. The radiation load was simulated by experimental implantation of 500keV H+ ions. The maximum radiation damage of 1 DPA was obtained across a region of 3 µm. Radiation-induced defects were investigated by coincidence Doppler broadening spectroscopy and positron lifetime spectroscopy using a conventional positron source as well as a slow positron beam. All techniques registered an accumulation of small open-volume defects (mostly mono- and di-vacancies) due to the irradiation, with an increase of the defect volume ΔVD ≈ 2.88 × 10−8 cm−3. Finally, the irradiated specimens were gradually annealed at temperatures from 200 to 550 °C and analyzed in detail. The best defect recovery was found at a temperature between 450 and 475 °C, but the final defect concentration of about ΔCD = 0.34 ppm was still higher than in the as-received specimens.

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“…Hence, the detailed microstructural evolutions in this thin irradiated layer (∼ µm) should be characterized by depth-sensing methods. PALS using variable mono-energy positron beams allows one to probe the depth profile of the surface and nearsurface defects in ion-irradiated structural materials and has been successfully applied to study microstructural evolutions in RPV steels [5][6][7][8]. In the past decades, a growing body of evidence showed that proton irradiation can emulate the neutron irradiation-induced microstructural features, which provides a basis for its use in screening new structural materials in current and advanced future reactors, while much less experiments have been done to benchmark Fe (i.e., self)-ion irradiation.…”

Section: Introductionmentioning

confidence: 99%

Positron Annihilation Studies of Reactor Pressure Vessel Steels Treated by Hydrogen Ion Implantation

et al. 2020

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Long term operation of nuclear reactors is one of the most discussed challenges in nuclear power engineering. Radiation degradation of nuclear materials limits the operational lifetime of all nuclear installations or at least decreases its safety margin. This paper is focused on experimental simulation and evaluation of materials via hydrogen ion implantation and on comparison with our previous results obtained from neutron-irradiated samples. In our case, German reactor pressure vessel (RPV) steels, originally from CARINA/CARISMA program, were studied by positron annihilation lifetime spectroscopy (PALS) and the pulsed low energy positron system (PLEPS) with the aim to study microstructural changes in RPV steels after high level of irradiation. Unique specimens were irradiated by neutrons in the German experimental reactor VAK (Versuchsatomkraftwerk Kahl) in the 1980s and these results were compared with the results from a high level of hydrogen nuclei implantation. Defects with sizes of about 1-2 vacancies with relatively small contributions (with intensity on the level of 20-40%) were observed in all "as-received" steels. An increase in the sizes of the induced defects (2-3 vacancies) due to neutron damage was observed in the irradiated specimens. On the other hand, the size and intensity of defects reached extremely high values due to displacement damage caused by implantation of hydrogen ions in a very narrow damaged region. This fact can be a limiting factor in the operation of new fission or fusion nuclear facilities.

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Integrated analysis of WWER-440 RPV weld re-embrittlement after annealing

Cited by 23 publications

References 26 publications

Radiation Damage of Reactor Pressure Vessel Steels Studied by Positron Annihilation Spectroscopy—A Review

Radiation Damage of Reactor Pressure Vessel Steels Studied by Positron Annihilation Spectroscopy—A Review

Positron Annihilation Study of RPV Steels Radiation Loaded by Hydrogen Ion Implantation

Positron Annihilation Studies of Reactor Pressure Vessel Steels Treated by Hydrogen Ion Implantation

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