National University of Science and Technology MISIS, Moscow, Russia

А. G. Mochugovsky, Associate Professor, Candidate of Technical Sciences, e-mail: mochugovskiy.ag@misis.ru
О. Troshkova, Laboratory Researcher
N. Yu. Тabachkova, Associate Professor, Candidate of Physical and Mathematical Sciences
E. N. Zanaeva, Associate Professor, Candidate of Technical Sciences
А. S. Prosviryakov, Senior Researcher, Candidate of Technical Sciences
А. V. Mikhailovskaya, Associate Professor, Candidate of Technical Sciences

The changes in the phase composition, microstructure parameters, and mechanical properties of the Al – Ti alloy system during mechanical alloying and subsequent hot pressing are studied. During mechanical alloying, Ti is dissolved in Al, which is accompanied by a decrease in the lattice constant (Al) to 0.4042 ± 0.0001 nm. The hardness of the alloy reaches a maximum value of 370 ± 20 HV, and the particle size of the powder reaches a minimum value of ~25 microns after 50 hours of grinding. Hot pressing at 450 оC of the mechanically alloyed powder for 50 hours has ensured effective consolidation. The pressing has been accompanied by the decomposition of a supersaturated aluminum-based solid solution and the formation of particles of phases D022-Al3Ti- and Al5Ti2. The obtained samples have a nanoscale structure and have increased thermal stability up to a temperature of 450 ^оC. The investigated alloy has a good combination of strength and ductility: compressive strength at room temperature is 460 MPa, at 350 ^оC – 170 MPa, relative deformation is at least 40%.
The research was carried out with the financial support of the Russian Science Foundation, grant No. 24-79-00092 (available at: https://rscf.ru/project/24-79-00092/).

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