In this work, the results of the irradiation of untreated, preliminarily Ar+-bombarded and Cr-coated samples of zirconium alloy E110 (Zr-1%Nb) with deuterium atoms and ions of deuterium plasma were ...compared with the results of their exposure to superheated water steam (673 K, 11 MPa; 673 K, 0.1 MPa; 633 K, 0.1 MPa). It was concluded that, despite of the difference in the rates of the oxide layer formation, the features of hydrogenation are similar under the two kinds of impact. However, the hydrogen uptake under irradiation occurs hundreds of times faster than during the steam test. The most effective hydrogenation was achieved under irradiation of the E110 sample with 300–500 eV/at ions of deuterium plasma without oxygen. These circumstances allow suggesting the irradiation with ions of hydrogen plasma as an accelerated hydrogenation test of zirconium alloys and protective coatings under conditions simulating the environment of light-water reactor's core. The proposed method could be realized using a simple plasma device and it does not require high power consumption or special qualification of staff.
•Features of zirconium hydrogenation in steam and in hydrogen plasma are similar.•Zirconium hydrogenation in plasma occurs hundreds of times faster than in steam.•Plasma irradiation can be used as accelerated out-of-core test of zirconium alloys.•Accelerated and steam tests of protective layers on zirconium give the same results.
The influence of irradiation in hydrogen plasma with oxygen impurity on the penetration of hydrogen isotopes through the surface of tungsten, through the surface of beryllium and aluminum layers on ...tungsten, and through the tungsten-coating interface was studied. It was shown that all these processes are accelerated in the presence of oxygen impurity in plasma. A conclusion is made that detritisation of the surface of both in the conditions of a fusion reactor tungsten and beryllium is possible.
An investigation on mechanisms of hydrogen and deuterium trapping in tungsten during irradiation by hydrogen ion plasma with oxygen impurity using the methods of thermal desorption spectrometry (TDS) ...and secondary ion mass spectrometry (SIMS) is presented in this paper. It was shown that almost 40% of trapped particles were retained in the surface oxide layer after first implantation of deuterium. Subsequent irradiation by hydrogen plasma with oxygen impurity lead to the increase of oxygen concentration and hydrogen trapping in the oxide layer and tungsten bulk. In the next cycle, which started with deuterium implantation, oxygen concentration in the oxide layer decreased and some hydrogen was removed from tungsten. Then an increase of hydrogen and oxygen concentration in the sample repeated during irradiation with ions of (H
2
+ 1 at. % O
2
) plasma. The same sequence of processes was observed during subsequent irradiation cycles.
The paper presents the results of investigation of gas exchange through stainless steel surface of the plasma chamber under irradiation with hydrogen atoms in oxygen atmosphere or oxygen contaminated ...hydrogen plasma. Dependence of this process on various irradiation parameters, such as the metal temperature, energy of irradiating ions, gas composition of plasma are studied. It is shown, that desorption from stainless steel is activated with the increase of the plasma chamber walls temperature and energy of irradiating ions. Hydrogen release occurs also under irradiation of the walls by helium and argon plasmas added with oxygen, however the amount of released hydrogen is several times lower than in the case of irradiation with oxygen contaminated deuterium plasma.
Features of plasma-induced formation of the surface oxide layers on zirconium alloy E110 (Zr-1%Nb) as well as hydrogen resistant properties of these layers are studied. It is shown that irradiation ...of the E110 sample with 1 keV ions of He + O2 plasma produces the oxide layer depleted by oxygen nearby the surface. The onset of the intensive hydrogen penetration into the ion-irradiated sample during the steam test (673 K, 0.1 MPa) appears to occur 1500 hours later than into the untreated one.
The results of the comparative analysis of low-temperature desorption of deuterium from tungsten coated with aluminum and yttrium films under the irradiation by hydrogen plasma with oxygen impurity ...are presented. The irradiation of aluminum or yttrium coating by H2+1%O2 plasma leads to the desorption of implanted deuterium from the samples. It was shown that the number of atoms desorbed depends on the sign of enthalpy of hydrogen solution in the metal film.
The results on trapping and desorption of hydrogen isotopes under irradiation of zirconium by deuterium atoms of thermal energies are presented. It is shown that the addition of oxygen to the ...operating gas during the irradiation causes the increase of the oxide layer thickness, the amount of hydroxyl groups in it and deuterium trapping in zirconium. Accelerated transport of deuterium atoms through the oxide layer saturated by hydroxyl groups is observed. Mechanisms of trapping and desorption of hydrogen isotopes and the role of oxygen in these processes are discussed.
•Mechanism of hydrogen transport under atomic irradiation of zirconium is proposed.•The addition of oxygen causes the growth of the oxide layer and the increase of deuterium trapping.•Oxygen diffusion to the bulk provokes hydrogen transfer from the bulk to the oxide layer.•Irradiation leads to hydrogen desorption from the oxide layer by formation of HDO molecules.•Saturation of the oxide layer by hydroxyl groups creates conditions for accelerated transport of deuterium.
In the paper, a simple and easy to operate stand is presented that allows irradiating the surface of solids by gas discharge plasma ions in the energies ranging from 5 to 40 keV. The results of first ...experiments are shown. Ion current parameters on the irradiated sample using gas discharge are presented for different gases.
The results of studying the trapping and retention of hydrogen and deuterium in MPG-8 graphite under sequential irradiation with ions of deuterium and hydrogen plasma are presented. The effect of the ...energy and density of the hydrogen-ion flux, the impurity of oxygen in the plasma, and the temperature of the irradiated samples on a decrease in the deuterium concentration and hydrogen trapping in graphite is studied. Based on the analysis of experimental data, it is suggested that the observed effect of deuterium removal can be explained by the chemical sputtering of graphite.
Effect of yttria and titanium nitride coatings on features of deuterium desorption from titanium layer is investigated. It is shown that both coatings significantly raise the temperature of maximum ...of deuterium thermal desorption from titanium under linear heating and prevent desorption under prolonged keeping at the operating temperature of a neutron tube target. However, under irradiation with ions of H2 + O2 plasma the barrier properties of titanium nitride appear to degrade.
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