National University of Science and Technology “MISiS”, Moscow, Russia:
V. V. Kurbatkina, Leading Researcher of the Scientific-Research Center of Self-Spreading High-Temperature Synthesis, e-mail: vvkurb@mail.ru
E. I. Pаtsera, Researcher of the Scientific-Research Center of Self-Spreading High-Temperature Synthesis
A. G. Bodyan, Master's Degree Student of a Chair of Powder Metallurgy and Functional Coatings
E. A. Levashov, Executive Officer of the Scientific-Research Center of Self-Spreading High-Temperature Synthesis, Head of a Chair of Powder Metallurgy and Functional Coatings

This paper investigates the peculiarities of self-spreading high-temperature synthesis with a stage of preliminary mechanical activation in Ti – Al system with functional additives. Increasing of the initial temperature (T₀) leads to the growth of mixture burning temperatures, which were measured with the T₀ = 670 ^oC. Structure and phase composition of initial mixtures and products of synthesis were investigated by X-ray phase analysis, scanning electron microscopy and energy disperse spectroscopy. There was investigated the influence of functional additives (NaCl, AlF₃, TiH₂, nitrocellulose [C₆H₇O₂(OH)_3–x(ONO₂)_x]_n and T₀) on structure and phase composition of synthesis products. Introduction of Ti and Al powders in stoichiometric mixture as energetic additive of nitrocellulose did not give any positive results, because the reaction is not complete, and the product contains titanium carbide. Investigations of influence of other additives on the synthesis temperature (T₀ = 670 ^оС), phase composition and structure of products showed the strong decrease of the burning temperature by AlF₃. The total content of formed titanium aluminides in TiH₂ is not higher than 51%. At the same time, the share of TiAl, containing not completely reacted initial components, is 9%. Introduction of NaCl lesser decreases the burning temperature than other additives. The product contains 78% of titanium aluminides, 12% of NaCl and 10% of Ti. The modes of obtained cakes grinding in rotating ball mill were defined, and provide the obtaining of narrow-fraction powders with the average size of particles of lesser then 5 μm.
This work was carried out with the financial support of the Ministry of Education and Science of Russian Federation within the state works in the sphere of scientific activity of the basic part of the state task No. 2014/113, НИР 28.58.

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