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A comparative analysis of the effect of high-pressure torsion (HPT) on the microstructure and tensile properties of the Al–10% La, Al–9% Ce, and Al–7% Ni model binary eutectic aluminum alloys is carried out. An HPT of 20-mm diameter specimens in as-cast state was carried out under constrained conditions, at room temperature, pressure P = 6 GPa, and number of turns N = 5. It is shown that the formation of nano- and submicrocrystalline structures and the refinement of eutectic particles in aluminum alloys simultaneously provide a multiple increase in strength while maintaining a high plasticity margin. This combination of properties has been achieved for the first time for severely deformed binary aluminum eutectics. The relationship between the type of eutectic particles, the structure formation process and the mechanical properties of the aluminum alloys has been established. The thermal stability of severely deformed aluminum alloys at heating up to 200 °C has been studied.

FSUE "All-Russian scientific research institute of aviation materials" RF SRC, Radio str. 17, 105005, Moscow, Russia Using transmission electron microscopy (TEM) method, the microstructure and phase composition of nickel based superalloy ZHS32 processed by selective laser melting (SLM) of a powder composition on a monocrystalline substrate and their evolution during heat treatment (HT) and hot isostatic pressing (HIP) by different regimes have been studied. Particular features of the microstructure formed during SLM, the distribution of chemical elements in cells and their boundaries have been explored. It has been established that the material after SLM has a unidirectional heterophase cell structure consisting of the matrix γ-solid solution, nanosized γ'-phase particles and a fine carbide phase at the cell boundaries. The influence of the HT and HIP temperature on the morphology and sizes of γ'-phase particles, the distribution of alloying elements between γ'-and γ-phases, the evolution of chemical composition, the type, size and distribution of carbide precipitates in the volume and boundaries of the cells after SLM have been studied. It has been shown that the alloy contains fine (Ta, Nb) C carbides with sizes up to 150 nm and carbides with sizes up to 1 µm, and (W, Cr) based carbides of the same sizes as well. The HIP process led to a formation of stacking faults on the phase boundaries between the γ-matrix and carbides. HT and HIP of SLM processed alloy ZHS32 has been shown to allow for obtaining a microstructure and phase composition typical for the single crystal alloy.Keywords: nickel base superalloy, selective laser melting, microstructure, γ'-phase, carbides, transmission electron microscopy, heat treatment, hot isostatic pressing.Микроструктура и фазовый состав жаропрочного сплава ЖС32 после селективного лазерного сплавления, вакуумной терми-ческой обработки и горячего изостатического прессования Заводов А. В. † , Петрушин Н. В., Зайцев Д. В.ФГУП «Всероссийский научно-исследовательский институт авиационных материалов», ул. Радио 17, 105005, Москва, РоссияМетодом просвечивающей электронной микроскопии (ПЭМ) проведены исследования эволюции микроструктуры и фазового состава жаропрочного никелевого сплава ЖС32, полученного методом селективного лазерного сплавле-ния (СЛС) порошковой композиции сплава на монокристаллической подложке, в процессе термической обработки (ТО) и горячего изостатического прессования (ГИП) по различным режимам. Изучены особенности формирую-щейся при СЛС микроструктуры и распределение химических элементов по ячейкам и их границам. Установлено, что материал после СЛС имеет однонаправленную ячеистую гетерофазную структуру, состоящую из матричного γ-твёрдого раствора, наноразмерных частиц γ'-фазы и дисперсных карбидных фаз, образовавшихся на границах ячеек. Исследовано влияние температуры ТО и ГИП на морфологию и размеры частиц γ'-фазы, распределение леги-рующих элементов между γ'-и γ-фазами, эволюцию химического состава, типа, размера и распределения карбидных выделений в объеме и на...