On athermic mechanism of materials radiation embrittlement

To elucidate the mehanisms of radiation embrittlement of materials the temperature dependence of mechanical properties of irradiated materials has been studiedyesBelgorod State Universit

On athermic mechanism of materials radiation embrittlement

yesTo elucidate the mehanisms of radiation embrittlement of materials the temperature dependence of mechanical properties of irradiated materials has been studiedBelgorod State Universit

On athermic mechanism of materials radiation embrittlement

To elucidate the mehanisms of radiation embrittlement of materials the temperature dependence of mechanical properties of irradiated materials has been studie

Compton-emissive hafnium detector of neutrons for in-core monitoring

The work is devoted to substantiating the use of metallic hafnium as the emitter of the Compton (prompt-response) in-core detector of thermal and resonant neutrons. The main trends in the development of nuclear power engineering, which raise the interest in the use of hafnium, are considered. The known data on the behavior of both Compton and β-emission self-powered neutron detectors (SPND) are generalized. The Compton SPND signal formation mechanism for the case of the irradiation by reactor-type fluxes of neutrons and gamma quanta is considered. The paper presents the calculation result of the hafnium burning-out degree for the conditions of WWER and RBMK reactors. The influence of the gamma radiation “sources”, which provide the largest contribution to the electrons production in the detector is considered

On athermic mechanism of materials radiation embrittlement

yesTo elucidate the mehanisms of radiation embrittlement of materials the temperature dependence of mechanical properties of irradiated materials has been studiedBelgorod State Universit

Модификация поверхности и распыление сплавов FeCrAl при воздействии низкоэнергетической одородной плазмы / Г. Д. Толстолуцкая, М. А. Тихоновский, В. Н. Воеводин, А. В. Никитин, А. С. Тортика, Р. Л. Василенко

In the present paper processes of sputtering and surface modification of commercial and experimental FeCrAl composites alloyed with yttrium, molybdenum and zirconium were investigated. Using a field-emission scanning electron microscope, it was shown that under the influence of low-energy (500 eV) hydrogen plasma with a flux about 3.2 ⋅ 1020 m–2 ⋅ s–1 and fluence 4 ⋅ 1024 m–2 at Troom, surface morphology develops due to the formation of grooves along grain boundaries, macro- and microcracks, as well as intragranular pits due to the sputtering of precipitates. Determination of the composition of precipitates by an energy dispersive X-ray spectrometer allowed to establish that aluminum oxide is preferentially distributed in the grains of FeCrAl-based alloys, and yttrium oxides are localized along grain boundaries. Results of erosion studies indicated that the sputtering yields for hydrogen on all alloys are 1.05– 0.38 at./ion and doesn’t exceed those for published data for pure iron and chromium. For experimental alloys doped with yttrium and molybdenum found that the obtained sputtering coefficients were in several times lower than for steel SS304 and only one and a half times higher compared to tungsten.В работе исследованы процессы распыления и модификации поверхности коммерческих и экспериментальных сплавов FeCrAl, легированных иттрием, молибденом и цирконием. С помощью сканирующей электронной микроскопии показано, что под воздействием низкоэнергетической (500 эВ) водородной плазмы с потоком около 3,2 ⋅ 1020 м–2 ⋅ с–1 и флюенсом 4 ⋅ 1024 м–2 при комнатной температуре морфология поверхности развивается вследствие образования канавок вдоль границ зерен, макро- и микротрещин, а также ямок, обусловленных распылением преципитатов. Определение состава последних энергодисперсионным рентгеновским спектрометром позволило установить, что оксид алюминия преимущественно распределен в зернах сплавов на основе FeCrAl, а оксиды иттрия локализованы по границам зерен. Результаты эрозионных исследований показали, что коэффициенты распыления для водорода у всех сплавов составляют 1,05– 0,38 ат./ион и не превышают таковых для чистого железа и хрома в опубликованных данных. Для экспериментальных сплавов, легированных иттрием и молибденом, получено, что коэффициенты распыления в несколько раз меньше, чем у стали SS304, и только в полтора раза выше по сравнению с вольфрамом