APPLICATION OF SHORT-WAVE DIFFRACTION OF SYNCHROTRON RADIATION FOR IN-SITU INVESTIGATION OF ZIRCONIUM HYDRIDES FORMATION AT GAS-PHASE HYDROGENATION
- Mr. Maxim SYRTANOV
- Mr. Maxim SYRTANOV (National Research Tomsk Polytechnic University, Tomsk, Russia)
- Mr. Victor KUDIIAROV (National Research Tomsk Polytechnic University, Tomsk, Russia)
- Mr. Egor KASHKAROV (National Research Tomsk Polytechnic University, Tomsk, Russia)
- Mr. Alexander SHMAKOV (Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia)
- Mr. Zakhar VINOKUROV (Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia)
Zirconium alloys are widely used as construction materials in an active zone of nuclear reactors. During operation of such alloys in contact with a hydrogen-containing environment, hydrogen penetrates into them. This significantly influences on the physical, chemical and mechanical properties of the material [1,2]. To investigate the effect of hydrogen accumulation on the zirconium alloys properties is necessary to prepare the experimental samples with different hydrogen concentrations and different distribution. However, the hydrogenation process can be hampered by the presence of a thin oxide film on the samples surface, which is greatly effect on the hydrogen distribution by material volume. The application of the nickel coating increases the hydrogen sorption rate. Also nickel has a high permeability to hydrogen. Moreover, the nickel oxidation is less active than zirconium, which contributes to hydrogen absorption.
In this paper zirconium alloy (Zr1%Nb) samples with a micron-order nickel layer were investigated. Hydrogenation was carried out by gas phase method at temperatures of 350, 450 and 550 ° C. Hydrogen pressure in chamber was 1 atm. Hydrogen sorption curves were obtained on the automated complex Gas Reaction Controller. In situ diffraction measurements were carried out in the process of hydrogen saturation of samples at the station "Precision diffractometry II» of the Institute of Catalysis of the Siberian Branch of the Russian Academy of Science at the 6 synchrotron radiation channel of the VEPP-3 electron storage ring.
Comparison of the data obtained in the analysis of hydrogen sorption curves with data of the phase transitions in the zirconium-hydrogen system at a gas phase hydrogenation allowed describing the processes occurring in zirconium by hydrogenation at different temperatures.
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