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Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393
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Документ Damaging of tungsten and tungsten–tantalum alloy exposed in ITER ELM-like conditions(Elsevier Inc., 2016) Makhlai, V. A.; Garkusha, I. E.; Linke, J.; Malykhin, S. V.; Aksenov, N. N.; Byrka, O. V.; Herashchenko, S. S.; Surovitskiy, S. V.; Wirtz, M.The damage of deformed double forged pure tungsten (W) and tungsten alloyed with 5 wt% tantalum (WTa5) have been studied in experimental simulations of ITER-like transient events with relevant surface heat load parameters (energy density up to 0.75 MJ/m 2 and the pulse duration of 0.25 ms) as well as particle loads (varied in wide range from 10 23 to 10 27 ion/m 2 s) with quasi-stationary plasma accelera- tor QSPA Kh-50. The plasma exposures were performed for the targets maintained at room temperature and preheated at 200 °C. The surface heat loads were either with no melting of W surface or above the melting threshold. The development of surface morphology of the exposed targets as well as cracking and swelling at the surface is discussed. Surface analysis was carried out with an optical microscopy and SEM. Surface modification and development of cracks led to increases of roughness of exposed surfaces. X-ray diffraction (XRD) has been used to study the micro-structural evolution of the exposed targets. The micro deformations of W and WTa5 are similar for targets exposed under similar conditions. The contri- bution of excess complexes of interstitial atoms in the formation of cracks after plasma irradiation was evaluated.Документ Erosion properties of tungsten and WTa5 alloy exposed to repetitive QSPA plasma loads below melting threshold(Національний науковий центр "Харківський фізико-технічний інститут", 2018) Makhlai, V. A.; Aksenov, N. N.; Byrka, O. V.; Garkusha, I. E.; Herashchenko, S. S.; Malykhin, S. V.; Surovitskiy, S. V.; Wirtz, M.; Sadowski, M. J.Документ Materials in conditions of high power plasma loads: surface damage and modification(Taras Shevchenko National University of Kyiv, 2018) Makhlai, V. A.; Aksenov, N. N.; Byrka, O. V.; Garkusha, I. E.; Chunadra, A. G.; Herashchenko, S. S.; Malykhin, S. V.; Sereda, K.; Surovitskiy, S. V.The paper discusses main features of material response to the repetitive powerful plasma impacts caused either the damage mechanisms and erosion behaviour or modification of surface layer and alloying with plasma species, aimed at improvement of material performance. Influence of powerful plasma impacts on several materials used for the construction of energy systems, i.e. steels as well as tungsten coatings, and pure tungsten has been discussed.Документ Features of surface modification of copper-based alloys under powerful plasma exposures(Національний науковий центр "Харківський фізико-технічний інститут", 2018) Byrka, O. V.; Aksenov, N. N.; Chunadra, A.; Herashchenko, S. S.; Makhlai, V. A.; Malykhin, S. V.; Sereda, K.; Surovitskiy, S. V.; Garkusha, I. E.Документ Materials surface damage and modification under high power plasma exposures(2018) Garkusha, I. E.; Makhlaj, V. A.; Byrka, O. V.; Taran, V. S.; Voitsenya, V.; Malykhin, S. V.; Herashchenko, S. S.; Surovitskiy, S. V.; Nowakowska-Langier, K.; Sadowski, M. J.; Skladnik-Sadowska, E.; Terentyev, D.Influence of powerful plasma impacts on several materials used for the construction of energy systems, i.e. different grades of steels as well as tungsten coatings, has been discussed. Irradiations of these materials with hydrogen and helium plasma streams have been performed in several high-current-pulse and quasi-stationary plasma accelerators which provided the variation of a power load upon the exposed surface as well as changes of the particle flux in wide ranges: the energy flux density in the range of 1-25 MJ/m2, particle flux - up to 1026-1029 ion/m2s, the plasma stream velocity - up to about 500 km/s, and the pulse duration in the range of 1-250 μs. A response of the investigated materials to extreme plasma loads, which are relevant to transient events in fusion reactors, is briefly discussed. It is demonstrated that a broad combination of mechanisms of powerful plasma interactions with various materials includes not only a surface damage caused by different erosion mechanisms, but under certain conditions it may also result in a significant improvement of material properties in the nearsurface surface layer of several tens μm in thickness. Some improvement of the structure and substructure of such a layer may be caused by the high-speed quenching, the shock wave formation and material alloying with plasma- and coating-species. The creation of unique surface structures and a considerable improvement of physical and mechanical properties of different materials can be achieved by the pulsed plasma alloying, i.e. pre-deposited coating modifications and mixing caused by the impacting plasma streams.Документ Alloying and modification of materials relevant to fusion and fission energy(Publications Office of the European Union, 2017) Makhlai, V. A.; Garkusha, I. E.; Byrka, O. V.; Taran, V. S.; Herashchenko, S. S.; Malykhin, S. V.Документ Modification, alloying and sputtering tests of Cr18Ni10Ti and EUROFER steels(Institute of Energy and Climate Research - Plasma Physics, 2017) Makhlai, V. A.; Garkusha, I. E.; Taran, V. S.; Voitsenya, V.; Herashchenko, S. S.; Aksenov, N. N.; Byrka, O. V.; Solyakov, D.; Solodovchenko, S.; Malykhin, S. V.; Surovitskiy, S. V.; Terentyev, D.Документ Structure evolution of tungsten coatings exposed to plasma flow under ITER ELM relevant conditions(Національний науковий центр "Харківський фізико-технічний інститут", 2016) Malykhin, S. V.; Surovitskiy, S. V.; Makhlaj, V. A.; Aksenov, N. N.; Byrka, O. V.; Borisova, S. S.; Herashchenko, S. S.; Reshetnyak, M. V.; Garkusha, I. E.Документ Alloying and modification of stainless steels by powerful plasma streams(Національний науковий центр "Харківський фізико-технічний інститут", 2016) Makhlaj, V. A.; Aksenov, N. N.; Byrka, O. V.; Chunadra, A. G.; Herashchenko, S. S.; Malykhin, S. V.; Mikhailov, I. F.; Sereda, K. N.; Surovitskiy, S. V.; Garkusha, I. E.Документ Damage of plasma-facing materials exposed to powerful plasma streams in ITER-relevant conditions(Київський національний університет ім. Тараса Шевченка, 2016) Makhlai, V. A.; Aksenov, N. N.; Byrka, O. V.; Garkusha, I. E.; Herashchenko, S. S.; Malykhin, S. V.The damage of tungsten (W) which is chosen as main plasma facing material relevant to International Thermonuclear Experimental Reactor (ITER) have been studied in experimental simulations of ITER-like transient events with quasi-stationary plasma accelerator QSPA Kh-50. Heat loads to exposed surfaces achieved 1 MJ/m2 (the pulse duration of 0.25 ms). The large and fine cracks appeared in result of plasma impacts. Heat loads accompanied by pronounced melting of tungsten cause an intense ejection of liquid droplets and solid dust. Re-deposition of the eroded material is observed also. The most important erosion mechanism connected with the edge effects in 3D geometry of targets has been studied. Such mechanism results in an increase in the size of the emitted droplets as compared with those emitted from a flat surface.