Search academic texts

Information × Registration Number 0220U102079, 0116U006497 , R & D reports Title Development and application of effective methods of determining resource products from zirconium alloys in conditions close to the conditions of operation of the reactor popup.stage_title Head Stoyev Petro I., Доктор фізико-математичних наук Registration Date 08-03-2020 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2  A batch of samples was made from Zr1% Nb alloy, which then underwent chemical-thermal treatment in controlled oxygen and nitrogen-containing media according to the regimes that were determined in the work. CTO significantly increases the hardness of the surface layer of zirconium alloy samples and does not lead to a decrease in mechanical properties and a noticeable change in the acoustic characteristics of the material. The near-surface modified layers that are formed in the samples during the СTO process in a nitrogen medium noticeably change the nature of the dependence of the growth increment on time throughout the course of oxidation. It has been established that the most effective СTO regimes for reducing the oxidation of samples from Zr1%Nb alloy are processing in a nitrogen medium. After processing the samples, the absolute values of additional weight, of the material during oxidation in air at 550° C for 100 hours decrease from 1.5 to 2.5 times, respectively, compared with untreated samples. It is shown that the chemo-chemical structure of zirconium alloy samples in an environment of oxygen and nitrogen helps to reduce the absorption of hydrogen samples. The most effective regime for the chemical-thermal treatment in oxygen was the regime: temperature 580°С and pressure P = 1•10-4 mm for 3.0 hours, which reduces hydrogen absorption by 3.3 times (to a concentration of 120ppm) compared to samples that did not pass СTO (400ppm). It is shown that surface modification of Zr1%Nb alloy tubes by СTO is one of the effective methods to reduce the influence of factors that lead to degradation of the properties of the metal of the tubes. The advantage of the developed method to increase the resource of the cladding of fuel rods is the possibility of using it in the existing technology by changing the heat treatment environment at the final stage of obtaining the tubes. Product Description popup.authors Efimov Oleksandr A. Andrіyevska Natalya F. Vasylʹyev Andriy O. Velikodnyi Oleksiy Mykolaiovych Kolodiy Igor V. Kondratov Oleksandr O. Mazin Oleksandr I. Panov Volodymyr A. Stoev Petro I. Tantsyura Iryna G. Tykhonovskyy Mykhaylo A. Tykhonovsʹka Tetyana M. popup.nrat_date 2020-04-02 Close