Effect of temperature and strain on the formation of elongated fine grained structure in middle carbon steel during large plastic deformation

The influence of deformation temperature and strain rate on the mechanisms of elongated fine grain (EFG) formation in the medium-carbon steel was studied. Compression tests were carried out at the temperatures in range of 673-973K at three different strain rates: 10-2, 1.3*10-3 and 10-4 s-1. Presence of two temperature intervals with different dominant mechanisms of deformation was identified: low temperature (673-823K) interval and high temperature (873-973K) interval. Microstructure evolution during deformation at strain rate of 1.3*10-3 s-1 and different temperatures was studied. Also was investigated the microstructure and mechanical properties of steel after warm plastic deformatio

Kinetics of grain refinemet in metallic materials during large strain deformation

The development of ultrafine grained microstructures in austenitic stainless steel and pure titanium subjected to large strain deformation was comparatively studied. The change in the volume fractions of newly developed ultrafine grains was used to quantify the progress in grain refinement during plastic deformatio

Microstructure evolution of commercial-purity titanium during cryorolling

Electron backscatter diffraction and transmission electron microscopy have been used to analyze the microstructural evolution of titanium during rolling at a cryogenic temperature (T = –196°C). It has been found that intensive twinning at the cryogenic deformation temperature accelerates the kinetics of micro structure refinement. The quantitative analysis of microstructure evolution in titanium upon cryorolling has shown that structure evolution is mainly related to mechanical twinning in the initial stages cryorolling is discusse

Effect of Mn and V on structure and mechanical properties of high-entropy alloys based on CoCrFeNi system

Microstructure and mechanical properties of equimolar composition alloys FeCrCoNi, FeCrCoNiV, FeCrCoNiMn and FeCrCoNiMnV were studied in as-solidified and annealed conditions. The FeCrCoNi and FeCrCoNiMn alloys were single-phase FCC solid-solutions in both conditions. However, the FeCrCo- NiV and FeCrCoNiMnV alloys consisted of the intermetallic r-phase matrix with a tetragonal crystal lattice and precipitates of a disordered FCC phase. The crystal structures of these alloys were found to be not affected by annealin

Structure and Properties of High Entropy Alloys

Высокоэнтропийные сплавы — сплавы, содержащие несколько основных элементов, с близкой к эквимолярной концентрацией. Рассматриваются особенности строения их структуры и физико-механических свойств. Показаны возможности получения более высокого уровня свойств высокоэнтропийных сплавов по сравнению с традиционными сплавами.High-entropy alloys — alloys containing several basic elements close to equimolar concentration. The report discusses the principles and algorithms for predicting new alloys, the features of their structure and physico-mechanical properties. The possibilities of obtaining a higher level of properties in comparison with traditional alloys are shown.Работа выполнена при финансовой поддержке РНФ (соглашение № 19-79-30066) с использованием оборудования Центра коллективного пользования «Технологии и материалы НИУ «БелГУ»».The work was carried out with the financial support of the RNF (Agreement No. 19-79-30066) using the equipment of the Center for Collective Use “Technologies and Materials of the National Research University BelSU”

HIGH ENTROPY ALLOYS — DEVELOPMENT, STRUCTURE AND PROPERTIES

High.entropy alloys — alloys containing several basic elements close to equimolar concentration. The report discusses the principles and algorithms for predicting new alloys, the features of their structure and physico.mechanical properties. The possibilities of obtaining a higher level of properties in comparison with traditional alloys are shown.Высокоэнтропийные сплавы — сплавы, содержащие несколько основных элементов, близких к эквимолярной концентрации. Рассматриваются принципы и алгоритмы прогнозирования новых сплавов, особенностей их структуры и физико-механических свойств. Показаны возможности получения более высокого уровня свойств по сравнению с традиционными сплавами.Работа выполнена при финансовой поддержке РНФ (Соглашение № 19-79-30066) с использованием оборудования Центра коллективного пользования «Технологии и Материалы НИУ «БелГУ»

Grain-structure development in heavily cold-rolled alpha-titanium

High-resolution electron back-scatter diffraction (EBSD) analysis was employed to establish mircostructure evolution in heavily cold-rolled alpha-titanium. After thickness reductions of 75% to 96%, significant microstructure and texture changes were documented. The surface area of high-angle grain boundaries was almost tripled, thus giving rise to an ultra-fine microstructure with a mean grain size of 0.6 μm. Moreover, orientation spread around typical ‘split-basal’ rolling texture substantially increased. These effects were suggested to be related to the enhancement of pyramidal 〈c+a〉 slip. Grain-structure development in heavily cold-rolled alpha-titanium (PDF Download Available

Effect of ECAP on microstructure and mechanical properties of Cu-₁₄Fe microcomposite alloy

In current study the Cu-14%(wt.)Fe alloy was subjected to 1-10 ECAP passes via route A and, in addition, to 4 passes via routes Bc and C. Microstructure of the alloy after ECAP was characterized using SEM and EBSD analysis. It was shown that the refinement of Fe particles largely depended on the processing route: route A was the most efficient and route Bc was the less efficient. After 10 passes via route A the average thickness of Fe particles decreased to about 3 μm from about 10 μm in initial state. However, the microstructure development in Cu matrix was found to be not dependent much on ECAP route – the average grain/subgrain reached value of about 0.25 μm (according to EBSD analysis) after 4 passes. The mechanical properties of the alloy were also found to be not sensitive to ECAP route

Structure and hardness of B2 ordered refractory AlNbTiVZr0.5 high entropy alloy after high-pressure torsion

High-pressure torsion (HPT) at room temperature was applied to an AlNbTiVZr0.5 refractory high entropy alloy. In the initial as-cast condition the alloy was composed of a coarse-grained B2 matrix phase and a continuous network of C14 Laves phase particles with the volume fraction of 19%. HPT resulted in the formation of a nanocrystalline structure in the B2 matrix with an average size of grains/subgrains of 25 nm after 5 revolution

Microstructure evolution and mechanical behavior of ultrafine Tie6Ale4V during low-temperature superplastic deformation

The influence of microstructure evolution on the low-temperature superplasticity of ultrafine Tie6Ale4V was established. For this purpose, the static and dynamic coarsening response and plastic-flow behavior of the alloy with a mean size of a (sub)grains and b particles of 0.1-0.4 μm were determined via a series of tension tests at temperatures between 450 and 700°