Browsing by Author "Trush, Vasyl"

Now showing 1 - 3 of 3

Kinetics of high-temperature interaction of titanium alloys with a carbon-containing gaseous medium
(Lviv Politechnic Publishing House, 2018-01-29) Trush, Vasyl; Luk’yanenko, Alexander; Karpenko Physico-Mechanical institute of the NAS of Ukraine
Due to their excellent complex of physical, chemical, and mechanical properties, titanium alloys are unique materials for many branches of industry. An important feature of titanium is its high reactivity concerning the interstitial chemical elements (oxygen, nitrogen, and carbon). The absorption of interstitial elements by titanium alloys causes change in physical and mechanical properties of alloys and articles which are made of them. It should be noted that the titanium alloys are classified, in particular, by the compositions of their structures. Investigations of titanium alloys of different structural compositions will enable us to take into account the influence of their features on the kinetics of their interaction with interstitial elements. Results of experimental investigations of the influence of a carbon-containing gaseous medium on the kinetics of interaction of titanium alloys of different structural classes (α-, pseudo-α, and (α+β)) are presented in this paper. It is established that the interaction at high temperatures (T = 750–850 °C) of titanium alloys with rarefied carbon-containing gaseous medium (Ar+16.7 % C3H8) under a pressure of P = 0.116 Pa leads to the increase in mass of the specimens according to a law which is close to linear dependence on time.
Oxidation and nitriding tubes of Zr-1%Nb zirconium alloy
(Lviv Polytechnic Publishing House, 2016) Trush, Vasyl; Luk’yanenko, Alexander; Chvalbota, Volodymyr; Karpenko Physico-Mechanical institute of the NASU; Lviv Polytechnic National University
The work presents results of saturation of Zr-1% Nb tubes after processing in oxygen- and nitrogen- containing gas environments. The distribution of micro-hardness in the thickness of the tube and the thickness of the hardened layers, the weight gain was determined. It is found that the oxidation of the Zr-1%Nb alloy (Т = 650°С, РО2=2.6·10-1 Pа, τ = 3…20 h) makes a greater weight gain than nitriding (Т = 650°С, τ = 5…20 h). The state of the surface of the inside and outside of Zr-1%Nb tubes for fuel cladding depending of the processings time was shown. The differences in saturation of outside and inside of the tube was showed. In particular, the hardness of internal surface of the tube is smaller relative to the outside after oxidizing and nitriding was found. The results of study of the outer and inner surface of fuel cladding in contact with gaseous environment containing oxygen and nitrogen are interesting for investigators of reactor materials.
Thermal processing of ZR-1 %NB tube in oxygenand nitrogen containing gaseous mediums
(Publishing House of Lviv Polytechnic National University, 2016) Trush, Vasyl; Luk’yanenko, Alexander; Fedirko, Viktor
Zirconium alloys have unique properties (physical, mechanical, radiation) is therefore are an essential structural material for nuclear energy. A feature of these alloys is high affinity to the interstitial elements (O, N). Saturation of oxygen and nitrogen occurs during the technological and exploitation heating. The dissolved interstitial elements greatly effect on the properties of finished products. The proposed results of experimental researches will expand the notions of patterns of relationship of the influence of elements interstitial on the properties of the zirconium alloy. The work presents results of the saturation of Zr-1 %Nb tubes after processing in oxygen- and nitrogen- containing gas environments. The distribution of micro-hardness and the size of the hardened layers in the section of the tube wall and the weight gain were determined. It is found that the oxidation of the Zr-1 %Nb alloy (Т = 650 °С, РО2 = 2.6·10-1 Pа, τ = 3…20 h) makes a greater weight gain than after nitriding (Т = 650 °С, τ = 5…20 h). The state of the surface of the inside and outside of Zr-1 %Nb tubes for fuel cladding depends of the processing time. The differences in saturation of outer and inner surfaces of the tube were registered. In particular, the hardness of internal surface of the tube is smaller relative to the outer surface after oxidation and nitriding processes. The results of study of the outer and inner surface of fuel cladding in contact with gaseous environment containing oxygen and nitrogen will be interesting for investigators of reactor materials.