IN-SITU INVESTIGATION OF THERMO-STIMULATED DISSOLUTION OF HYDRIDES IN TITANIUM AND ZIRCONIUM BY MEANS OF SHORT-WAVE DIFFRACTION OF SYNCHROTRON RADIATION
- Dr. Roman LAPTEV
- Dr. Roman LAPTEV (National Research Tomsk Polytechnic University)
Titanium and zirconium alloys are widely used in medicine, chemical and oil industries, aircraft industry, in nuclear power industry. Hydrogen penetration and accumulation in titanium and zirconium products lead to its properties and can lead to the delayed fracture due to the hydrogen embrittlement [1-4].
Degree of hydrogen impact on the titanium and zirconium properties depends on its concentration and condition in metal. Hydrogen saluted in lattice has a low impact on properties of the metal. However, hydrogenation under operation of titanium and zirconium alloys often occurs with hydrides formation. As a consequence, investigation of hydrides formation and dissociation in titanium and zirconium has both fundamental and practical interest.
Samples of commercially pure titanium alloy and Zr1%Nb zirconium alloy were instigated in this work. Hydrogenation was done by gas-phase method at temperature 600 °C and hydrogen pressure 1 atm. Spectrum of hydrogen thermo-stimulated desorption from samples after hydrogenation were obtained with the help of automated complex Gas Reaction Controller LPB with mass-spectrometer RGA100.
In situ diffraction measurements were carried out in the process of samples heating 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 desorption curves with data of the phase transitions in the zirconium-hydrogen and titanium-hydrogen systems at the heating allowed describing the processes occurring in zirconium and titanium hydrides under thermal treatment.
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