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Since 1994, the Ukrainian Phase Diagrams and Thermodynamics Commission has been a part of the Alloy Phase Diagram International Commission (APDIC), in which 18 representatives from 26 countries of the world participate in its activities. The exchange of scientific information and coordination of activities of the international scientific community, mainly in the field of phase diagrams and thermodynamics, promoting the application of phase diagrams in industry and fundamental science, and dissemination of the methodology of critical evaluation of scientific information in world science are among the priority tasks of the APDIC's activity. As part of the annual report of the Ukrainian Commission, at the APDIC meeting on June 30, 2023, information was presented on the results of the activities of Ukrainian scientists in this field in 2022. It is presented in the form of a table with data on the studied systems and obtained results and a list of references to published papers. Scientists from the Frantsevich Institute for Problems of Materials Science (National Academy of Sciences of Ukraine, Kyiv), Taras Shevchenko National University of Kyiv (Ministry of Education and Science of Ukraine, Kyiv), and Donbas State Engineering Academy (Ministry of Education and Science of Ukraine, Kramatorsk) provided relevant information to the Ukrainian Commission. [ABSTRACT FROM AUTHOR]

The Ukrainian Phase Diagrams and Thermodynamics Commission has been a member of the Alloy Phase Diagram International Commission (APDIC) for almost thirty years (since 1994). APDIC unites 18 member organizations involving 26 countries. The main tasks of APDIC are the exchange of scientific information and coordination of the activities of the international scientific community, mainly in the field of state diagrams and phase thermodynamics. The annual report of the Ukrainian Commission on the results of the activities of Ukrainian scientists in this field in 2021 was presented at the APDIC meeting on May 27, 2022. This information is presented in a table, collecting data on the systems studied and the result obtained and containing a list of references to published papers. Scientists from the Frantsevich Institute for Problems of Materials Science (National Academy of Sciences of Ukraine, Kyiv), Taras Shevchenko National University of Kyiv (Ministry of Education and Science of Ukraine, Kyiv), and Donbas State Engineering Academy (Ministry of Education and Science of Ukraine, Kramatorsk) provided relevant information to the Ukrainian Commission. [ABSTRACT FROM AUTHOR]

The main tasks of the international scientific organization Alloy Phase Diagram International Commission (APDIC), which unites 18 member organizations involving 26 countries, are the exchange of information and coordination of the activities of the international scientific community, mainly in the field of phase diagrams and thermodynamics. The Ukrainian Phase Diagrams and Thermodynamics Commission has been a member of APDIC since 1994. The annual report of the Ukrainian Commission on the results of the activities of Ukrainian scientists in this field in 2020 was presented at the APDIC meeting on June 18, 2021, which was held online due to the coronavirus pandemic. This information is presented in a table, collecting data on the studied systems and obtained result and containing a list of references to published papers. Scientists from the Frantsevich Institute for Problems of Materials Science (National Academy of Sciences of Ukraine, Kyiv), Taras Shevchenko National University of Kyiv (Ministry of Education and Science of Ukraine, Kyiv), and Donbas State Engineering Academy (Ministry of Education and Science of Ukraine, Kramatorsk) provided relevant information to the Ukrainian Commission. [ABSTRACT FROM AUTHOR]

Phase equilibria during solidification in the Al-Cr-Co system in the range of compositions 0-70 at.% Al were studied using optical microscopy, scanning electron microscopy, electron probe microanalysis, differential thermal analysis and x-ray diffraction. Solidus and liquidus surfaces, a melting diagram as their superposition, a Scheil diagram for solidification, as well as series of isopleths were constructed for the first time. Solid solutions based on Cr, αCo, Cr5Al8 (γ3 and γ1 phases), CoAl, Co2Al5 binary compounds and the ternary compound τ5 take part in phase equilibria. The monoclinic ternary compound τ5 forms by peritectic reaction L + γ1 + Co2Al5 ↔ τ5 at 1065 °C. Four invariant four–phase reactions and one invariant three–phase reaction involving liquid take place at 1280, 1175, 1110, 1065 and about 1480 °C, respectively. Isopleths 10, 20, 30 and 40 at.% Al as well as 40 at.% Cr demonstrate peculiarities of the phase diagram. [ABSTRACT FROM AUTHOR]

Physicochemical analysis results for alloys in the Al–Ti–Pt system at 0–50 at.% Pt that were cast and annealed at subsolidus temperatures are used to construct for the first time vertical sections at 7, 25, and 35 ± 1 at. Pt of this system taking into account the constitution of its melting diagram. The congruent crystallization of τ3, τ 4, and τ8 compounds and incongruent crystallization of τ2 and τ5 compounds are confirmed. Changes from incongruent to congruent crystallization of the solid solutions based on binary Al3Pt2, Al2Pt, and TiAl phases in transition to the ternary system are shown. [ABSTRACT FROM AUTHOR]

The melting diagram and reaction scheme (Scheil diagram) of the Al–Ti–Pt system have been constructed for the first time in the composition range 0–50 at.% Pt using the experimental results for as-cast alloys and alloys annealed at subsolidus temperatures. It is established that ternary compounds τ3, τ4, and τ8 form congruently with participation of the liquid phase and compounds τ1, τ2, τ5, τ6, τ7, τ9, and τ11 by peritectic reactions. All compounds take part in phase equilibria with participation of the liquid phase, forming 31 four-phase and 28 three-phase invariant equilibria at temperatures from 1410 to 660°C. [ABSTRACT FROM AUTHOR]

The liquidus surface of the Al–Ti–Pt system has been constructed for the first time on the composition triangle based on studies of the structure and phase composition and measurement of the liquidus temperatures for the as-cast alloys in the composition range 0–50 at.% Pt produced using a series of techniques. The liquidus surface has 23 primary crystallization fields corresponding to τ1–τ9 and τ11 ternary phases and binary phases formed in the boundary systems and to solid solutions based on components. The extension of these fields and the positions of univariant curves and invariant points have been determined. The liquidus surface exists in the temperature range from 1830°C (corresponding to congruent melting of TiPt compound) to 655°C (temperature of the l ⇄ + 21Pt5> eutectic in the binary Al–Pt system). [ABSTRACT FROM AUTHOR]

The nature of phase equilibria has been examined for the first time in the Al–Ti–Pt system in the range 0–50 at.% Pt at subsolidus temperatures. Besides the τ1, τ2, and τ3 ternary compounds with AuCu3, Th6Mn23+1, and MgZn2 lattices known from the literature, eight more compounds form in the system at subsolidus temperatures. The structural type is known for three of these compounds. They are τ4 (ZrBeSi), τ5 (CrFe), and τ6 (defective structure of Au4Al type). There are 31 isothermal planes on the solidus surface. All planes are formed with participation of ternary compounds and solid solutions based on binary compounds present in the boundary systems. The highest temperature in this composition range corresponds to the congruent melting of the TiPt phase (1830°C) and the lowest to eutectic l ⇄ + in the binary Al–Pt system (655°C). [ABSTRACT FROM AUTHOR]

A correction to this paper has been published: https://doi.org/10.1007/s11669-021-00891-z [ABSTRACT FROM AUTHOR]