scholarly journals Investigation of Helium Behavior in RAFM Steel by Positron Annihilation Doppler Broadening and Thermal Desorption Spectroscopy

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1523
Author(s):  
Zhenyu Shen ◽  
Liping Guo ◽  
Weiping Zhang ◽  
Shuoxue Jin ◽  
Xingzhong Cao ◽  
...  
Keyword(s):  
Positron Annihilation ◽  
Thermal Desorption ◽  
Thermal Desorption Spectroscopy ◽  
Binding Energies ◽  
Doppler Broadening ◽  
Martensitic Steels ◽  
Helium Bubbles ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Rafm Steel

The behavior of helium in reduced-activation ferritic/martensitic steels was investigated systematically with positron annihilation Doppler broadening measurement and thermal desorption spectroscopy. Specimens were irradiated with helium ions with different energies to various fluences at different temperatures. A threshold fluence was observed above which the rate of formation and growth of helium bubbles dramatically increased. Irradiation at higher temperature could suppress the formation and growth of HenVm clusters with low binding energies and enhance that of helium bubbles and HenVm clusters with high binding energies. Different changes of S parameters were observed in various depth after the irradiation temperature was increased from 523 K to 723 K. Irradiation of 18 keV-He+ enhanced the growth of HenVm clusters and helium bubbles compared with 100 keV-He+ irradiation. A possible mechanism is discussed.

Annealing Behaviour of Helium Bubbles in Titanium Films by Thermal Desorption Spectroscopy and Positron Beam Analysis

2007 ◽  
Vol 24 (8) ◽  
pp. 2357-2360 ◽  
Author(s):  
Liu Chao-Zhuo ◽  
Zhou Zhu-Ying ◽  
Shi Li-Qun ◽  
Wang Bao-Yi ◽  
Hao Xiao-Peng ◽  
...  
Keyword(s):  
Thermal Desorption ◽  
Thermal Desorption Spectroscopy ◽  
Positron Beam ◽  
Helium Bubbles ◽  
Annealing Behaviour ◽  
Beam Analysis

The synergies between displacement damage creation and hydrogen presence: the effect of D ion energy and flux

2022 ◽  
Author(s):  
Sabina Markelj ◽  
Matic Pečovnik ◽  
Thomas Schwarz-Selinger ◽  
Mitja Kelemen
Keyword(s):  
Nuclear Reaction ◽  
Thermal Desorption ◽  
Rate Equation ◽  
Irradiation Time ◽  
Thermal Desorption Spectroscopy ◽  
Nuclear Reaction Analysis ◽  
Displacement Damage ◽  
Ion Energy ◽  
Depth Profiles ◽  
Different Temperatures

Abstract In this work the synergism between displacement damage creation and presence of hydrogen isotopes was studied. Tungsten samples were irradiated by 10.8 MeV W ions with or without the presence of D ions with two different energies of 300 eV/D and 1000 eV/D and different temperatures. In order to compare the results obtained with different exposure parameters the samples were afterwards additionally exposed to D ions at 450 K to populate the created defects. By increasing the W irradiation time, ion flux and energy, the increase of D concentration and D retention was observed as measured by nuclear reaction analysis and thermal desorption spectroscopy. By fitting the D depth profiles and D desorption spectra by the rate equation code MHIMS-R we could see that additional fill-levels were populated with higher flux and ion energy which ends up in higher final D concentration and retention as compared to experiments with lower D flux and energy.

scholarly journals Helium implanted RAFM steels studied by positron beam Doppler Broadening and Thermal Desorption Spectroscopy

2013 ◽  
Vol 443 ◽  
pp. 012034 ◽  
Author(s):  
I Carvalho ◽  
H Schut ◽  
A Fedorov ◽  
N Luzginova ◽  
P Desgardin ◽  
...  
Keyword(s):  
Thermal Desorption ◽  
Thermal Desorption Spectroscopy ◽  
Positron Beam ◽  
Doppler Broadening

Study of the Hydrogen Traps in a High Strength TRIP Steel by Thermal Desorption Spectroscopy

2012 ◽  
Vol 706-709 ◽  
pp. 2253-2258 ◽  
Author(s):  
Diana Pérez Escobar ◽  
Lode Duprez ◽  
Kim Verbeken ◽  
Marc Verhaege
Keyword(s):  
Grain Boundaries ◽  
Thermal Desorption ◽  
Trip Steel ◽  
Cold Deformation ◽  
Thermal Desorption Spectroscopy ◽  
High Strength ◽  
Trip Steels ◽  
Depth Study ◽  
Different Temperatures ◽  
Steel Trip700

Thermal desorption spectroscopy (TDS) is a very important tool in hydrogen related research. It allows to distinguish between the different types of microstructural hydrogen traps based on the analysis of the different temperatures at which hydrogen desorbs from the material during heating. These peak temperatures depend on the metallurgical and microstructural characteristics of the steel under investigation and provide important information on the possible mechanisms for hydrogen embrittlement (HE). In the present work, multiple TDS experiments and an in-depth study of the microstructure were performed on a TRIP steel (TRIP700) that was previously cold deformed in order to make a correlation between the microstructural features of this material, e.g. grain boundaries, dislocations, martensite formation and the peaks that became visible during TDS. The results obtained for the TRIP grade were compared with those obtained for electrolytic pure iron, which only contained a limited amount of possible trap sites such as grain boundaries and an increasing amount of dislocations due to previous application of cold deformation. Significant differences between both materials and a significant impact of the degree of cold deformation for TRIP steels were observed.

scholarly journals Improved Accuracy of Thermal Desorption Spectroscopy by Specimen Cooling during Measurement of Hydrogen Concentration in a High-Strength Steel

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1252 ◽  
Author(s):  
Eric Fangnon ◽  
Evgenii Malitckii ◽  
Yuriy Yagodzinskyy ◽  
Pedro Vilaça
Keyword(s):  
Thermal Desorption ◽  
Hydrogen Concentration ◽  
High Strength Steel ◽  
Vacuum Chamber ◽  
Thermal Desorption Spectroscopy ◽  
High Strength ◽  
Steel Sample ◽  
Martensitic Steels ◽  
Hydrogen Flux ◽  
Redistribution Of Hydrogen

Thermal desorption spectroscopy (TDS) is a powerful method for the measurement of hydrogen concentration in metallic materials. However, hydrogen loss from metallic samples during the preparation of the measurement poses a challenge to the accuracy of the results, especially in materials with high diffusivity of hydrogen, like ferritic and ferritic-martensitic steels. In the present paper, the effect of specimen cooling during the experimental procedure, as a tentative to reduce the loss of hydrogen during air-lock vacuum pumping for one high-strength steel of 1400 MPa, is evaluated. The results show, at room temperature, the presence of a continuous outward hydrogen flux accompanied with the redistribution of hydrogen within the measured steel during its exposure to the air-lock vacuum chamber under continuous pumping. Cooling of the steel samples to 213 K during pumping in the air-lock vacuum chamber before TDS measurement results in an increase in the measured total hydrogen concentration at about 14%. A significant reduction in hydrogen loss and redistribution within the steel sample improves the accuracy of hydrogen concentration measurement and trapping analysis in ferritic and martensitic steels.

scholarly journals Thermal Effect on the Structural, Electrical, and Optical Properties of In-Line Sputtered Aluminum Doped Zinc Oxide Films Explored with Thermal Desorption Spectroscopy

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Shang-Chou Chang ◽  
Tien-Chai Lin ◽  
To-Sing Li
Keyword(s):  
Zinc Oxide ◽  
Optical Properties ◽  
Thermal Effect ◽  
Thermal Desorption ◽  
Thermal Desorption Spectroscopy ◽  
Optical Transmittance ◽  
Device Fabrication ◽  
Electrical And Optical Properties ◽  
Different Temperatures ◽  
Aluminum Doped Zinc Oxide

This work investigates the thermal effect on the structural, electrical, and optical properties of aluminum doped zinc oxide (AZO) films. The AZO films deposited at different temperatures were measured using a thermal desorption system to obtain their corresponding thermal desorption spectroscopy (TDS). In addition to obtaining information of thermal desorption, the measurement of TDS also has the effect of vacuum annealing on the AZO films. The results of measuring TDS imply part of the doped aluminum atoms do not stay at substituted zinc sites in AZO films. The (002) preferential direction of the AZO films in X-ray diffraction spectra shifts to a lower angle after measurement of TDS. The grain size grows and surface becomes denser for all AZO films after measurement of TDS. The carrier concentration, mobility, and average optical transmittance increase while the electrical resistivity decreases for AZO films after measurement of TDS. These results indicate that the AZO films deposited at 200°C are appropriate selections if the AZO films are applied in device fabrication of heat-produced process.

Helium Behaviour in Fe-Base Materials: Thermal Desorption and Nuclear Reaction Analyses

2012 ◽  
Vol 323-325 ◽  
pp. 221-226 ◽  
Author(s):  
Hélène Lefaix-Jeuland ◽  
Sandrine Miro ◽  
Fabrice Legendre
Keyword(s):  
Nuclear Reaction ◽  
Thermal Desorption ◽  
Depth Profiling ◽  
Bulk Diffusion ◽  
Thermal Desorption Spectroscopy ◽  
Reaction Model ◽  
Nuclear Reaction Analysis ◽  
Helium Bubbles ◽  
Base Materials ◽  
Complementary Set

Polycrystalline Fe 99.95 and 99.5 samples were implanted with helium at 8 keV and 3 MeV. Thermal Desorption Spectroscopy (TDS) and Nuclear Reaction Analysis (NRA) provided a complementary set of techniques to characterize helium-materials interactions within two different implantation depths, respectively close to the surface and in the bulk. Using TDS, it was possible to get information about the nature and the states of the structures where helium was trapped in radiation damaged Fe specimens. Activation energies for every trapping site (mono-vacancies, clusters) have been determined from conventional reaction model. The effect of interstitial carbon was also discussed, and compared with previous ab-initio studies. Moreover, the helium bulk diffusion constants in radiation damaged structures could be derived from non destructive 3He depth profiling. Preliminary observations highlighted that a few part of He remained trapped while helium bubbles migrated in the bulk.

Helium implanted Eurofer97 characterized by positron beam Doppler broadening and Thermal Desorption Spectroscopy

2013 ◽  
Vol 442 (1-3) ◽  
pp. 377-381 ◽  
Author(s):  
I. Carvalho ◽  
H. Schut ◽  
A. Fedorov ◽  
N. Luzginova ◽  
P. Desgardin ◽  
...  
Keyword(s):  
Thermal Desorption ◽  
Thermal Desorption Spectroscopy ◽  
Positron Beam ◽  
Doppler Broadening
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