Кафедра теорії, технології та автоматизації металургійних процесів (ДМетІ НФ)

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http://crust.ust.edu.ua/handle/123456789/15109
ENG: Department of Theory, Technology and Automation of Metallurgical Processes

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Browsing Кафедра теорії, технології та автоматизації металургійних процесів (ДМетІ НФ) by Author "Balakhanova, T. V."

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    Experimental Study on the Influence of Vibrational Processing in the Course of Ballistic Testing of Metal Plates
    (Printing House “Technologija”, Kaunas, Lithuania, 2024) Havryliak, V. R.; Sviridov, S. O.; Balakin, Valerii F.; Balakhanova, T. V.
    ENG: The continuous increase in requirements for armored materials necessitates not only the development of new materials but also the enhancement of the resilience of traditional ones. An analysis of existing data identified a positive effect of vibrational processing on the level of residual stresses in materials, and also revealed the impact of plate deviation along coordinate axes on its ballistic characteristics. This work investigated the effect of vibrational processing on the ballistic properties of 30CrNi2Mo grade steel plates with a thickness of 6.5 mm. Following the ballistic tests, macro- and microstructural examinations of the samples were conducted, along with measurements of microhardness. The feasibility of vibration application was confirmed experimentally. It was determined that without the application of vibration, 100% of the studied samples failed the tests, resulting in a hole at the point of impact. More than 50% of the samples, which were subjected to vibration at frequencies of 10 and 20 Hz during the ballistic tests, were not destroyed. A dent formed at the point of impact. It is shown that the application of vibration significantly enhances the ballistic characteristics of 30CrNi2Mo grade steel plates. The characteristics of the bullet impact traces depend on the vibration frequency. No correlation with the amplitude of oscillation was found at this stage of the work. Analysis of the holes formed during the ballistic tests showed an increase in the plastic component during perforation. Metallographic studies revealed bright lines in the structure of the samples, which in their characteristics are similar to adiabatic shear bands. The use of vibration facilitates the deformation of the bullet, changes the morphology of perforation/deformation, which is confirmed by metallographic analysis.
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    Improving the Corrosion Resistance of Hot-Rolled Steel Pipes
    (Sergeieva&Co, Karlsruhe, Germany, 2023) Bohdan, D. A.; Balakin, Valerii F.; Balakhanova, T. V.; Kuznetsov, Yevhen V.; Nykolayenko, Yuliia М.
    ENG: Purpose. Substantiation of the use of surface plastic and dynamic surface deformation (SPD, DSD) combined with anticorrosion inhibitory treatment of general-purpose carbon steel pipes to increase wear resistance of pipelines. Methodology. Samples of hot-formed steel taken from test pipe fragments were subjected to various modes of surface plastic and dynamic surface deformation using corrosion inhibitors. Plastic deformation was carried out with a brush tool with different values of brush pressing against the pipe and processing time. Studies of the protective ability of inhibitors were carried out by an accelerated method with periodic moisture condensation according to DSTU ISO 6270-2:2015. A comparative metallographic study of the metal structure of pipes subjected to PPD and DPD with inhibitors was carried out. Results. The results of experimental studies of the surface corrosion resistance and metallographic structure of 139x5 mm pipes made of steel grade 20 using three types of inhibitors and various modes of dynamic plastic deformation are presented. Scientific novelty. The dynamic surface deformation of metal, which refines its grain structure, creates conditions for formation of "penetration channels" for the inhibitor into the metal structure. The use of DPD makes it possible to reduce the grain size in the surface layer, which suggests possibility of controlling the depth of the inhibitor penetration and, as a result, the corrosion resistance of pipes, depending on the operational requirements. Practical value. It has been established that the use of dynamic surface deformation in combination with a certain inhibitor makes it possible to increase the corrosion resistance by 11–19 times.