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Temperature dependence of kinematic viscosity of Fe12Mn2C liquid alloy was determined. Results are discussed in context of microheterogeneity of FeMnC alloys within the framework of theory of absolute reaction rates. [ABSTRACT FROM AUTHOR]

Corrosion properties of type 625 alloys (Inconel 625 and Nicrofer 6020) in chloroaluminate melts were investigated in a wide range of temperatures and various exposure time intervals using gravimetric tests and energy- dispersive X-ray spectroscopy of corroded samples surface. It was shown that corrosion processes have electrochemical nature and the increase of temperature up to 650 °C leads to change of corrosion mechanism from gradual etching towards intergranular corrosion. Intergranular destruction is associated with the formation of secondary phases at the grain boundaries of alloys. "Time-temperature-precipitation" diagram was constructed to predict the possible conditions of type 625 alloys application. It was found that Inconel 625 and Nicrofer 6020 alloys can be used in contact with chloaluminate melts at temperatures less than 600 °C. [ABSTRACT FROM AUTHOR]

Evolution of the structure and the phase composition, microhardness, contact modulus of elasticity after quenching, further multi-pass cold rolling with a total reduction ratio of 85 % of the hot-worked rods was studied for Ti- 39Nb-5Zr, Ti-39Nb-5Zr-2Sn, Ti-39Nb-5Zr-2Sn-2Ta alloys (composition in wt. %). [ABSTRACT FROM AUTHOR]

Analysis of the literature data on the properties of high-entropy alloys based on the Al-Cr-Mn-Fe system was performed. The results allowed evaluating the prospects for the synthesis of high-entropy alloys in Al-Cr-Mn-Fe-(Ti, Zr, V, Nb, Ta) systems. The results of modeling the Al-Ti-Cr-Mn-Fe alloy by ab initio molecular dynamics showed that the formation of a high-entropy alloy is possible. In this alloy, both in terms of partial pair functions of the radial distribution and analysis of the size of atoms, an ordered solid solution can be formed. After analyzing the data obtained from the calculations, we can assume a high probability of formation of intermetallides Al-Ti, Mn-Ti, Fe-Ti and Fe-Al. [ABSTRACT FROM AUTHOR]

Physical and chemical properties of Ti-Al-(Nb, Ta, V) alloys obtained by joint aluminothermic reduction of metals from the oxides were studied. It was found that an increase in temperature from 1500 to 1625 °C contributed to a linear decrease in the density and surface tension of the alloys. Increasing concentration of Nb, Ta and V to 3.5 mol. % affected the increase in the values of these properties. [ABSTRACT FROM AUTHOR]

The main indicator of ferroalloy efficiency is the degree of absorption of the driving element, which is greatly influenced by physical and chemical properties of the ferroalloy: melting start and end temperature, ferroalloy density, melting duration of ferroalloy and its thermal characteristics. Studying the effect of the chemical composition of ferroalloy on its service characteristics makes possible to predict the degree of assimilation of its leading elements by the steel. The pycnometric method was used to determine density of boron-containing ferroalloys. The density was in the range of 3.8–4.64 g/cm3. Reduction of silicon content to 40–55 wt. % contributes to the density increase, bringing it closer to the range of rational values. The study of the melting point of alloys showed that all alloys were low-melting with a melting point of below 1200 °C. By using a mathematical model, the melting time of ferroalloy was calculated. It is shown that the rational diameter for alloys is 10–20 mm. [ABSTRACT FROM AUTHOR]

The interaction of the introduced dispersed refractory particles in the metal during its smelting is simulated in order to obtain composite materials that are resistant to the interaction of radionuclides. The simulation was carried out in the FactSage 7.0 software package. the results of modeling the interaction of the metal phase with yttrium oxide, tungsten carbide, and titanium carbide are Presented. The simulation results showed that even if the added additives do not have time to dissolve when interacting with the metal phase, the iron turns into an oxide melt. It is shown that the components of metal alloys, such as manganese, titanium and chromium, will also be oxidized along with the oxide melt. [ABSTRACT FROM AUTHOR]

This work is devoted to the influence of intergrain exchange interaction on the magnetic hysteresis properties of nanocrystalline composite alloys considering Pr-Fe-B alloy as an example. The appearance of an inflection on the major hysteresis loops of such alloys at lower temperatures is demonstrated and explained. The values of effective coercivity of hard and soft magnetic phases are estimated. It is shown that because of not considering the reduction of the exchange interaction constant on the phase boundary, the Kneller-Hawing's model does not describe hysteresis magnetic properties of composite exchange-coupled materials well enough. [ABSTRACT FROM AUTHOR]

The results of testing method of synthesis of a high-entropy AlNbTiVZr alloy using metallothermic reduction of group IV and V metals from their oxides are presented. At the first stage, joint aluminothermic reduction of metals was performed in a resistance furnace. Then, to achieve uniformity and remove harmful impurities, the metal was remelted in a vacuum furnace with an inert atmosphere. The alloy obtained after the second remelting was subjected to chemical and x-ray phase analysis. The results of the analysis revealed the presence of a solid solution of Zr (Nb, V) with TiAl inclusions, confirming the prospect of using metallothermic synthesis to produce a high-entropy alloy with a single-phase structure. [ABSTRACT FROM AUTHOR]