| 2026 №02 (06) |
DOI of Article 10.37434/sem2026.02.07 |
2026 №02 (01) |
"Suchasna Elektrometallurgiya" (Electrometallurgy Today), 2026, 2, 57-64 pages
Influence of heat treatment on the structure of VT9 alloy
V.Yu. Bilous1
, E.L. Vrzhizhevskyi1, R.V. Selin1, L.M. Radchenko1, S.L. Antoniuk2
1E.O. Paton Electric Welding Institute of the NAS of Ukraine
11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.
E-mail: belousvy@gmail.com
2SC «O.K.Antonov ANTK». 1 Mriya Str., 03062, Kyiv, Ukraine
Abstract
High-temperature titanium two-phase (α+β)-alloys can have high service properties when used in aircraft engines. In order to widen the scope of application or to restore the parts made from two-phase VT9 alloy, it is rational to consider the possibility of applying vacuum annealing for processing of the billets or parts after machining or welding. The influence of vacuum annealing at the temperature of 950 °C on the structure of sheets of VT9 titanium (α+β)-alloy was studied in the work. Sheets of VT9 titanium (α+β)-alloy 10 mm thick, were treated by vacuum annealing at the temperature of 950 °С for 1 h and were cooled with the furnace. Microstructure of the metal of samples of high-temperature two-phase titanium(α+β)-alloy VT9 in the initial condition is homogeneous, finely dispersed and consists of α-phase particles, with a thickness of 2…4 μm, and length of 2…20 μm. Microstructure of the metal of samples after vacuum annealing with further cooling with the furnace is homogeneous, and it consists of α-phase particles with a thickness of 2…6 μm and a length of up to 20 μm. An increase in the dimensions of the α-phase is noted, which is related to the process of its coagulation. Vacuum annealing at the temperature of 950 °С led to reduction of the number of dispersed particles in the metal structure and growth as a result of coagulation, during slow cooling of the α-phase particles. The quantity of the β-phase in the metal of the high-temperature titanium (α+β)-alloy VT9 decreases to 15...22 %. Such structural changes may lead to lowering of the alloy strength values and increase in the impact toughness values, which promotes an increase in service properties of parts from VT9 alloy. 19 Ref., 3 Tabl., 8 Fig.
Keywords: titanium alloy, two-phase (α+β)-alloys, microstructure, vacuum annealing, α-phase, β-phase
Received: .04.2026
Received in revised form: 11.05.2026
Accepted: 20.05.2026
Posted online: 27.05.2026
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Suggested Citation
V.Yu. Bilous, E.L. Vrzhizhevskyi, R.V. Selin, L.M. Radchenko, S.L. Antoniuk (2026) Influence of heat treatment on the structure of VT9 alloy. Electrometallurgy Today, 02, 57-64. https://doi.org/10.37434/sem2026.02.07Advertising in this issue:
