2018 №03 (04) DOI of Article
2018 №03 (06)

Electrometallurgy Today 2018 #03
Electrometallurgy Today (Sovremennaya Elektrometallurgiya), 2018, #3, 32-38 pages

Properties of alloys on titanium aluminide γ-TiAl/α2-Ti3Al base at complex alloying

S.A. Firstov1, I.D. Gornaya1, Yu.N. Podrezov1, A.A. Bondar1, A.V. Sheremetjev2

1I.N. Frantsevich Institute of Problems of Materials Science of the NAS of Ukraine.3 Krzhyzhanovsky Str., 03142, Kyiv. E-mail: dir@ipms.kiev.ua
2SE «Ivchenko-Progress». 2 Ivanov Str., 69068, Zaporozhye. E-mail: progress@ivchenko-progress.com

Presented are the results of study of effect of a complex alloying by Nb (3...4 %), Mo, Cr, Zr (up to 2 %), B, Y (up to 0.2 %) on mechanical properties of cast intermetallic γ-TiAl/α2-Ti3Al alloys, containing from 44.0 up to 48.5 % Al, produced by the method of vacuum arc remelting. The mechanical properties were determined at bending, uniaxial tension and compression tests. Vickers hardness and long-time hot hardness (high-temperature strength) were measured. The tests were carried out within the temperature interval of 20...800 °С. It was shown that the optimum properties during tension at 20 and 700 °С were demonstrated by the cast alloy Ti–47Al–5.5 (Nb, Cr, Mo); coefficient of elasticity was approximately 170 and 126 GPa, tensile strength was 770 and 644 MPa, ductility was 0.15 and 0.65 %, respectively. Crack resistance of this alloy is approximately 22.4 MPa∙m1/2, long-time hot hardness at 700 °С is 2.0 GPa, that twice increases the value of hardness of high-temperature titanium alloys. 20 Ref., 5 Tabl., 1 Fig.
Key words: titanium alloys; titanium aluminides; alloying; mechanical properties; high-temperature strength
Received:                09.07.17
Published:               01.10.18

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