Bondar A. Phase diagrams of systems formed by d-metals with p-elements of III and IV groups as a scientific basis for development of materials with high specific strength in a wide temperature range.

The thesis is devoted to construction of phase diagrams of ternary systems Al-Fe-Ta, Al-Ті-Х, where Х is Nb, Та, Cr, or С, and В-Ті-Z, where Z is Al, Si, Ge, Sn, V, Nb, or Мо, as well as a number of binary boundary systems. Parameters of phase equilibria and characteristics of phase transformations in insufficiently studied regions of ternary systems Al-Fe-Ta, Al-Nb-Ti, Al-Та-Tі, Al-Cr-Ti, Al-C-Ti, Al-B-Ti, B-Nb-Ti, and B-Мо-Ti and binary Al-Ti, Al-Nb, Al-Ta, B-Ti, B-Nb and Fe-Ta ones. For these systems and also for Al-Cr and B-Мо ones, thermodynamic descriptions were elaborated by using a CALPHAD approach on the basis of assessed experimental data, and phase diagrams were calculated. Systems B-Si-Ti, B-Ge-Ti, B-Sn-Ti, and B-Ti-V were studied in the Ti-rich regions, and phase diagrams were constructed for them. Modes of presentation in a reaction scheme after Scheil were proposed for invariant and monovariant reactions with the participation of continuous transformations (chemical and magnetic orderings). Hardness and strength characteristics are examined and discussed for selected alloys based on TiAl and eutectics. Some features of phase diagrams of systems Al-Ті-dM and B-Ті-dM, where dM is d-metal of V and VI groups, are discussed, which are of interest for development of low-density high-temperature alloys.