Synthesis of titanium hydrides and obtaining of alloys based on them

In the present work prepared and studied a series of sample composition with variation ratios of the elements, wt.%: 100% Ti, 50% Ti: 50% Al, 44.2% Ti : 55.8% Al, 39.5% Ti: 60.5% Al, 36.7% Ti: 63.3% Al, 34.31% Ti: 65.7% Al, 23.5% Ti: 76.5% Al, 100% Al. As raw materials, a sponge titanium was used, which was prepared from the corresponding hydride. The obtained titanium hydride mixed with aluminum na-nopowder (average particle size (115 ± 10) nm, specific surface area value (19,4 ± 3) m / g, an aluminum content of - (80.8 ± 0.6)%) and compacted under pressure (10-20) MPa. Round shaped tablet was annealed in a vacuum system in a programmed mode until temperature (800-1050)°C. X-ray diffraction (XRD) of the composites based on titanium performed on diffractometer Rigaku Miniflex 600 using CuKa-radiation in the range of 10-90° (20) with a pitch and speed of scanning 0,02° shooting 2 deg/min. XRF method established education thermodynamically stable in-termetallic phases: TiAl, TiAl ₂, TiAl ₃, Ti ₃Al. Using the stoichiometric ratio Ti: Al in the initial mixture (3 : 1) afforded material containing agglomerates of fine-grained particles sintered intermetallic TiAl. At other molar ratios is possible to obtain two-phase and three-phase systems containing intermetallic TiAl, TiAl ₂, TiAl ₃. Present in the sample phase Ti ₃Al and TiAl is due to the thermodynamics of phase formation. Formation of these phases is characterized by a minimum standard Gibbs energy of formation. All the phases correspond to the state diagram and are characterized by similar lattice parameters corresponding reference values. The article describes a kind of symmetry, the nature of the space group, the lattice parameters are given for all phases of the synthesized alloys of Ti-Al. It is shown that all the phases are OCD to 100 nm. This fact shows that the selected method can be difficult to obtain a composition containing dispersed intermetallic phases of Ti-Al. Based on the results and XRD data generating circuit built phase composition of Ti-Al system by varying the mass of aluminum content and annealing temperature.

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