Superplasticity of titanium aluminides

R. Imayev, V. Imayev


In the present paper, processing methods and superplastic properties of fine-grained γ - TiAl+α2-Ti3Al based intermetallic alloys with varying alloy composition have been considered. It has been demonstrated that superplastic behavior is feasible in single-phase (γ-TiAl and α-Ti3Al), two-phase (γ-TiAl+α2-Ti3Al) and three-phase (γ-TiAl+α2-Ti3Al+β(B2)) alloys. Superplastic properties in the single-phase alloys were reached due to the fact that diffusion processes occur slower in intermetallic alloys in contrast to pure metals; this impeded dynamic grain growth during superplastic flow and promoted superplastic elongations. It has been revealed that processing required for manufacturing of a fine-grained condition is dependent on the alloy composition and can be simplified at transition from peritectically solidifying γ-TiAl+α2-Ti3Al based alloys to β-solidifying ones. The use of β -solidifying alloys, which are known to have better chemical homogeneity in contrast to peritectically solidifying γ-TiAl+α2-Ti3Al based alloys, provided enhanced superplastic characteristics. Highest superplastic elongations (up to δ=1000% at T=1000°C and εʹ≈10-3 s-1) were obtained for the β-solidifying alloy (Ti-45Al-5Nb-1Mo-0.2B, at. %) containing a small amount of the β(B2)-phase and subjected to single-step hot forging. Interestingly, superplastic properties were even attained in the as-cast β-solidifying alloy containing around 20 vol. % of the β(B2) phase without any prior hot working.

Accepted: 20 April 2015

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M. S. Kim, S. Hanada, S. Watanabe, O. Izumi. Mat. Trans. JIM. 30(1), 77 (1989).
R. M. Imayev and V. M. Imayev. Scr. Met. 25, 2041 (1991).
3. T. Takasugi, S. Rikukawa and S. Hanada. Proceed. Intern. Conf.«Superplasticity in Advanced Materials», edit. S. Hori, M. Tokizaneand N. Furushiro, Jap. Soc. Res. Superplast. (1991), p. 329.
T. Takasugi, S. Rikukawa and S. Hanada. Acta Metal. 40, 1895 (1992).
T. Maeda, M. Okada and Y. Shida. Proceed. Intern. Conf.Superplasticity in Advanced Materials, edit. by Hori S., Tokizane M.and Furushiro N. Jap. Soc. Res. Superplast. (1991) p. 311.
R. M. Imayev, O. A. Kaibyshev and G. A. Salishchev. Acta Metal. 40,581 (1992).
S. C. Cheng, J. Wolfenstine and O. D. Sherby. Metal Trans. 23A, 1509 (1992).
R. M. Imayev, G. A. Salishchev, V. M. Imayev, N. K. Gabdullin andM. R. Shagiev. Mater. Sci. Forum. 170—172, 453 (1994).
R. S. Mishra, W. B. Lee, A. K. Mukherjee. Proceed. Intern. Conf.Gamma Titanium Aluminides, ed. by Y.‑W. Kim, R. Wagner, M. Yamaguchi.The Minerals, Metals & Mater. Soc. 571 (1995).
C. M. Lombard, A. K. Ghosh and S. L. Semiatin. Proceed. Intern.Conf. Gamma Titanium Aluminides, ed. by Y.‑W. Kim, R. Wagner, M.Yamaguchi. The Minerals, Metals & Mater. Soc. 579 (1995).
R. Imayev, M. Shagiev, G. Salishchev, V. Imayev and V. Valitov.Scr. Mat. 34, 985 (1996).
V. M. Imayev, R. M. Imayev, G. A. Salishchev. Mater. Sci. Eng.A208, 226 (1996).
R. Imayev, N. Gabdullin and G. Salishchev. Intermetallics. 5, 229 (1997).
A. K. Mukherjee and R. S. Mishra. Mater. Sci. Forum. 243—245, 609 (1997).
V. M. Imayev, G. A. Salishchev, M. R. Shagiev, A. V. Kuznetsov, R.M. Imayev, O. N. Senkov and F. H. Froes. Scr. Mat. 40, 183 (1999).
R. M. Imayev, G. A. Salishchev, O. N. Senkov, V. M. Imayev, M. R.Shagiev, N. K. Gabdullin, A. V. Kuznetsov, F. H. (Sam) Froes. Mater.Sci. Eng. A300, 263 (2001).
O. A. Kaibyshev. Superplasticity of commercial alloys. Moscow:Metallurgy, 276 p. (1984). (in Russian)
V. M. Imayev, R. M. Imayev, A. V. Kuznetsov. Proc. Symp. «GammaTitanium Aluminides». TMS. San Diego, USA. 311 (2004).
V. M. Imayev, R. M. Imayev, A. V. Kuznetsov. Scr. Mat. 49, 1047 (2003).
V. M. Imayev, R. M. Imayev, T. I. Oleneva, T. G. Khismatullin. ThePhysics of Metals and Metallography. 106 (6), 641 (2008).
R. Safiullin, R. Imayev, V. Imayev, W. Beck, Froes F. H. (Sam),and G. Salishchev. Mater. Sci. Forum. 551—552, 441 (2007).
V. M. Imayev, T. G. Khismatullin, W. Beck, V. Güther, H.‑J. Fecht.Scr. Mater. 57, 193 (2007).
V. Imayev, R. Imayev, T. Khismatullin, T. Oleneva, V. Guhter,H.‑J. Fecht. Mater. Sci. Forum. 638—642, 235 (2010).
V. M. Imayev, T. G. Khismatullin, R. M. Imayev. The Physics ofMetals and Metallography. 109 (4), 402 (2010).
J. N. Wang, Y. Wang. Inter. J. of Plasticity. 22, 1530 (2006).
R. Imayev, V. Imayev, M. Oehring, F. Appel. Intermetallics. 15, 451 (2007).
H. Clemens and S. Mayer. Adv. Eng. Mater. 15, 191 (2013).
R. M. Imayev, N. K. Gabdullin, G. A. Salishchev, O. N. Senkov, V.M. Imayev and F. H. Froes. Acta Mater. 47, 1809 (1999).