As revealed by studies, in the process of high-pressure torsion of hard or work-hardenable metals and alloys, including bulk metallic glasses, the actual produced strain is much smaller than the expected one. The authors proposed a new technique called “accumulative high-pressure torsion” for producing high strains in hard materials, including bulk metallic glasses.

The microstructure and mechanical properties of the Zr 62 Cu 22 Al 10 Fe 5 Dy 1 bulk metallic glass (BMG) processed by high pressure torsion (HPT) at temperatures of 20° and 150°С were investigated. Transmission electron microscopy and XRD studies did not reveal any structural transformations. The material in both initial amorphous state and after HPT processing demonstrates brittle fracture under uniaxial tensile testing at temperatures in the range of 20 -300°C. The maximum fracture stress of the material in the initial state is 1410 MPa. Fracture stress of the HPT-processed states is lower in comparison with that of the initial state due to the presence of microcracks in the HPT-processed samples. The values of the maximum fracture stress are 250 and 1240 MPa for the samples processed by HPT at 20° and 150°С, respectively. Fracture surfaces of the material in the initial state and after HPT processing have different morphologies due to structural transformations induced by HPT processing. Annealing of the samples in the initial state and after HPT processing results in smaller grain size in the HPTprocessed samples in comparison with the initial samples. However, microindentation reveals that hardness of the material in the initial state after annealing is noticeably higher than hardness of the HPT processed alloy after the same annealing. Thus, it can be outlined that HPT processing affects the microstructure evolution in the material during further annealing. Исследована микроструктура и механические свойства аморфного сплава Zr 62 Cu 22 Al 10 Fe 5 Dy 1 , подвергнутого воз-действию интенсивной пластической деформации кручением (ИПДК) при температуре 20° и 150°С. Методом про-свечивающей электронной микроскопии и РСА не удалось выявить каких-либо структурных изменений. Образ-цы аморфного сплава до и после ИПДК при испытаниях на растяжение при различных температурах, включая 300°С, разрушаются хрупко. В исходном аморфном состоянии максимальное напряжение разрушения составляет 1410 МПа. Максимальные напряжения разрушения составляют 250 и 1240 МПа для образцов после ИПДК при 20° и 150°С, соответственно. Однако вид излома после испытаний на растяжение образцов до и после ИПДК несколько различается, что отражает изменение структуры в результате ИПДК. Размер зерна в сплаве, подвергнутому ИПДК и отжигу заметно меньше, чем сплава, подвергнутого отжигу из исходного состояния, а микротвердость сплава, подвергнутого ИПДК и отжигу заметно ниже, чем Hv отожжённого исходного образца. Таким образом, предвари-тельная ИПДК, видимо, меняет эволюцию структуры при последующем кристаллизационном отжиге.Ключевые слова: аморфные сплавы, интенсивная пластическая деформация, структуры, механические свойства.

High-pressure torsion allows one to achieve high strains of bulk metal glasses without their destruction. The article presents the results of studies on the effect of high-pressure torsion on the amorphous alloys of the same composition but obtained in different ways: in a form of a bulk plate and a melt-spun ribbon. It is shown that the degree of nonequilibrium after high-pressure torsion, determined by the diffraction and calorimetry methods, increases for bulk metallic glass, approaching the values characteristic for melt-spun alloy.

In the presented article, the features of the structure and function, morphological and morphometric parameters of the main structures of the spleen, which belongs to the peripheral organ of the immune system, are studied, the patterns of development of this organ at the stages of postnatal ontogenesis are revealed. The article analyzes the data of domestic and foreign literature on the influence of environmental factors on structural changes in the spleen at the organ, tissue and cellular levels. Further study of the spleen will make it possible to identify and analyze the patterns of their structural and functional changes when exposed to a genetically modified product (soybeans).

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