Hostname: page-component-8448b6f56d-tj2md Total loading time: 0 Render date: 2024-04-23T08:17:30.849Z Has data issue: false hasContentIssue false
  • English
  • Français

First-principles study of deformation-induced phase transformations in Ti–Al intermetallics

Published online by Cambridge University Press:  31 January 2011

C.L. Chen ,
W. Lu ,
L.L. He  and
H.Q. Ye
L.L. He*
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
H.Q. Ye
Affiliation:
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China; and Electron Microscope Laboratory, Peking University, Beijing 100871, China
*
a) Address all correspondence to this author. e-mail: llhe@imr.ac.cn
Get access

Abstract

The structural phase stability and electronic properties of the Ti–Al intermetallic compounds were investigated by means of density-functional theory (DFT) calculations in a generalized gradient approximation. Through comparison of the calculated formation energies of the parent and product phases, an in-depth theoretical understanding of the deformation-induced γ ↔ α2 phase transitions observed previously in TiAl alloys was achieved. The formation energy plays an important role in evaluating the feasibility of these phase transformations during plastic deformation of TiAl alloys. In addition, the density of states (DOS) was also calculated and used to analyze the stability of Ti–Al intermetallic compounds. The reasons for the absence of the deformation-induced (DI)-α2 and DI-γ (L12) phases in underformed TiAl alloys were analyzed.

Keywords

AlloyPhase transformation
Type
Articles
Information
Journal of Materials Research , Volume 24 , Issue 5 , May 2009 , pp. 1662 - 1666
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Kim, Y.W. and Dimiduk, D.M.: Progress in the understanding of gamma titanium aluminides. JOM 43, 40 (1991).CrossRefGoogle Scholar
2.Kim, Y.W.: Ordered intermetallic alloys, Part III: Gamma titanium aluminides. JOM 96, 30 (1994).CrossRefGoogle Scholar
3.Appel, F., Sparka, U., and Wagner, R.: Work hardening and recovery of gamma base titanium aluminides. Intermetallics 7, 325 (1999).Google Scholar
4.Maruyama, K., Yamaguchi, M., Suzuki, G., Zhu, H.L., Kim, H.Y., and Yoo, M.H.: Effects of lamellar boundary structural change on lamellar size hardening in TiAl alloy. Acta Mater. 52, 5185 (2004).CrossRefGoogle Scholar
5.Appel, F. and Wagner, R.: Microstructure and deformation of two-phase γ-titanium aluminides. Mater. Sci. Eng., R 22, 187 (1998).CrossRefGoogle Scholar
6.Kempf, M., Goken, M., and Vehoff, H.: The mechanical properties of different lamellae and domains in PST-TiAl investigated with nanoindentations and atomic force microscopy. Mater. Sci. Eng., A 329–331, 184 (2002).CrossRefGoogle Scholar
7.Appel, F., Oehring, M., and Wagner, R.: Novel design concepts for gamma-base titanium aluminide alloys. Intermetallics 8, 1283 (2000).CrossRefGoogle Scholar
8.Yang, R., Cui, Y.Y., Dong, L.M., and Jia, Q.: Alloy development and shell mould casting of gamma TiAl. J. Mater. Process. Technol. 135, 179 (2003).CrossRefGoogle Scholar
9.Wu, X.H.: Review of alloy and process development of TiAl alloys. Intermetallics 14, 1114 (2006).Google Scholar
10.Wegmann, G. and Maruyama, K.: On the microstructural stability of TiAl/Ti3Al polysynthetically twinned crystals under creep conditions. Philos. Mag. A 80, 2283 (2000).CrossRefGoogle Scholar
11.Kim, H.Y. and Maruyama, K.: Stability of lamellar microstructure of hard orientated PST crystal of TiAl. Acta Mater. 51, 2191 (2003 ).CrossRefGoogle Scholar
12.Huang, Z.W., Voice, W.E., and Bowen, P.: Thermal stability of Ti–46Al–5Nb–1W alloy. Mater. Sci. Eng., A 329–331, 435 (2002).Google Scholar
13.Gao, Y., Zhu, J., Shen, H.M., and Wang, Y.N.: Stress-induced phase transformation in two-phase TiAl intermetallic alloys. Scr. Metall. Mater. 28, 651 (1993).CrossRefGoogle Scholar
14.Feng, C.R., Michel, D.J., and Crowe, C.R.: Microstructural characteristics of two-phase titanium aluminides. Mater. Sci. Eng., A 145, 257 (1991).Google Scholar
15.Wang, J.G., Zhang, L.C., Chen, G.L., Ye, H.Q., and Nieh, T.G.: Deformation-induced γ ↔ α2 phase transformation in a hot-forged Ti-45Al-10Nb alloy. Mater. Sci. Eng., A 239–240, 287 (1997).Google Scholar
16.Derder, C., Bonnet, R., Penisson, J.M., and Frommeyer, G.: Evidence of stress-induced α2 → γ transformation in a Ti–30at.%Al alloy. Scr. Mater. 38, 757 (1998).CrossRefGoogle Scholar
17.Zhang, Y.G., Ticheaar, F.D., and Schapink, F.W., Xu, Q., and Chen, C.Q.: An evidence of stress- induced α2 → γ transformation in a γ-TiAl-based alloy. Scr. Metall. Mater. 32, 981 (1995).CrossRefGoogle Scholar
18.Zhang, J.X. and Ye, H.Q.: Deformation-induced α2 → γ phase transformation in a Ti-48Al-2Cr alloy. J. Mater. Res. 15, 2145 (2000).CrossRefGoogle Scholar
19.Chen, C.L., Lu, W., He, L.L., and Ye, H.Q.: Deformation-induced γ → DI-α2 phase transformation occurring in the twin-intersection region of TiAl alloys. J. Mater. Res. 22, 2416 (2007).Google Scholar
20.Chen, C.L., Lu, W., He, L.L., and Ye, H.Q.: Deformation-induced γ → DI-α2 phase transformation of TiAl alloys. J. Chin. Electr. Microsc. Soc. 26, 276 (2007).Google Scholar
21.Chen, C.L., Lu, W., Lin, J.P., He, L.L., Chen, G.L., and Ye, H.Q.: Deformation-induced α2 → γ phase transformation in TiAl alloys. (under review).Google Scholar
22.Payne, M.C., Teter, M.P., Allan, D.D., Arias, T.A., and Johannopoulos, J.D.: Iterative minimization techniques for ab initio total-energy calculations: Molecular dynamics and conjugate gradients. Rev. Mod. Phys. 64, 1045 (1992).CrossRefGoogle Scholar
23.Hohenberg, P. and Kohn, W.: Inhomogeneous electron gas. Phys. Rev. B 136, 864 (1964).CrossRefGoogle Scholar
24.Kohn, W. and Sham, L.J.: Self-consistent equations including exchange and correlation effects. Phys. Rev. A 140, 1133 (1965).Google Scholar
25.Vanderbilt, D.: Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. Phys. Rev. B 41, 7892 (1990).Google Scholar
26.Perdew, J.P. and Wang, Y.: Accurate and simple density functional for the electronic exchange energy: Generalized gradient approximation. Phys. Rev. B 33. 8800 (1986).CrossRefGoogle ScholarPubMed
27.Pack, J.D. and Monkhorst, H.J.: “Special points for Brillouin-zone integrations”—A reply. Phys. Rev. B 16, 1748 (1977).CrossRefGoogle Scholar
28.Liu, Y.L., Liu, L.M., Wang, S.Q., and Ye, H.Q.: First-principles study of shear deformation in TiAl and Ti3Al. Intermetallics 15, 428 (2007).CrossRefGoogle Scholar
29.Srivastava, G.P., Martins, J.L., and Zunger, A.: Atomic structure and ordering in semiconductor alloys. Phys. Rev. B 31, 2561 (1985).Google Scholar
30.Wei, S.H., Mbaye, A.A., Ferreira, L.G., and Zunger, A.: First-principles calculations of the phase diagrams of noble metals: Cu–Au, Cu–Ag, and Ag–Au. Phys. Rev. B 36, 4163 (1987).CrossRefGoogle ScholarPubMed
31.Liu, Y.L., Liu, L.M., Wang, S.Q., and Ye, H.Q.: First-principles study of shear deformation in TiAl alloys. J. Alloys Compd. 440, 287 (2007).CrossRefGoogle Scholar
32.Xu, J.H., Oguchi, T., and Freeman, A.J.: Solid-solution strengthening: Substitution of V in Ni3Al and structural stability of Ni3(Al, V). Phys. Rev. B 36, 4186 (1987).Google Scholar
33.Hong, T., Watson-Yang, T.J., Freeman, A.J., Oguchi, T., and Xu, J.H.: Crystal structure, phase stability, and electronic structure of Ti–Al intermetallics: TiAl3. Phys. Rev. B 41, 12462 (1990).CrossRefGoogle ScholarPubMed
34.Hong, T., Watson-Yang, T.J., Guo, X.Q., Freeman, A.J., Oguchi, T., and Xu, J.H.: Crystal structure, phase stability, and electronic structure of Ti–Al intermetallics: Ti3Al. Phys. Rev. B 43, 1940 (1991).CrossRefGoogle ScholarPubMed