Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Impurities block the α to ω martensitic transformation in titanium

Abstract

Impurities control phase stability and phase transformations in natural and man-made materials, from shape-memory alloys1 to steel2 to planetary cores3. Experiments and empirical databases are still central to tuning the impurity effects. What is missing is a broad theoretical underpinning. Consider, for example, the titanium martensitic transformations: diffusionless structural transformations proceeding near the speed of sound2. Pure titanium transforms from ductile α to brittle ω at 9 GPa, creating serious technological problems for β-stabilized titanium alloys. Impurities in the titanium alloys A-70 and Ti–6Al–4V (wt%) suppress the transformation up to at least 35 GPa, increasing their technological utility as lightweight materials in aerospace applications. These and other empirical discoveries in technological materials call for broad theoretical understanding. Impurities pose two theoretical challenges: the effect on the relative phase stability, and the energy barrier of the transformation. Ab initio methods4,5 calculate both changes due to impurities. We show that interstitial oxygen, nitrogen and carbon retard the transformation whereas substitutional aluminium and vanadium influence the transformation by changing the d-electron concentration6. The resulting microscopic picture explains the suppression of the transformation in commercial A-70 and Ti–6Al–4V alloys. In general, the effect of impurities on relative energies and energy barriers is central to understanding structural phase transformations.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Structural phase transitions in titanium.
Figure 2: Impurity sites in α and ω.
Figure 3: Impurities change the energy barrier of the α → ω transformation.

Similar content being viewed by others

References

  1. Otsuka, K. & Wayman, C. M. (eds) Shape Memory Materials (Cambridge Univ. Press, 1998).

    Google Scholar 

  2. Olson, G. B. & Owen, W. S. (eds) Martensite (ASM, Metals Park, Ohio, 1992).

    Google Scholar 

  3. Vočadlo, L. et al. Possible thermal and chemical stabilization of body-centred-cubic iron in the Earth's core. Nature 424, 536–539 (2003).

    Article  Google Scholar 

  4. Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558–561 (1993).

    Article  CAS  Google Scholar 

  5. Jónsson, H., Mills, G. & Jacobsen, K. W. In Classical and Quantum Dynamics in Condensed Phase Simulations (eds Berne, B. J., Ciccotti, G. & Coker, D. F.) 385–404 (World Scientific, Singapore, 1998).

    Book  Google Scholar 

  6. Vohra, Y. K. Electronic basis for omega phase stability in group IV transition metals and alloys. Acta Metall. 27, 1671–1674 (1979).

    Article  CAS  Google Scholar 

  7. Jayaraman, A., Klement, J. W. & Kennedy, G. C. Solid-solid transitions in titanium and zirconium at high pressures. Phys. Rev. 131, 644–649 (1963).

    Article  CAS  Google Scholar 

  8. Zilbershtein, V. A. et al. Alpha-omega transition in titanium and zirconium during shear deformation under pressure. Fiz. Met. Metalloved. 39, 445–447 (1975).

    CAS  Google Scholar 

  9. Vohra, Y. K., Sikka, S. K., Vaidya, S. N. & Chidambaram, R. Impurity effects and reaction kinetics of the pressure-induced alpha to omega transformation in Ti. J. Phys. Chem. Solids 38, 1293–1296 (1977).

    Article  CAS  Google Scholar 

  10. Gray, G. T., Morris, C. E. & Lawson, A. C. In Titanium '92: Science and Technology (eds Froes, F. H. & Caplan, I. L.) 225–232 (TMS, Warrendale, 1993).

    Google Scholar 

  11. Sikka, S. K., Vohra, Y. K. & Chidambaram, R. Omega phase in materials. Prog. Mater. Sci. 27, 245–310 (1982).

    Article  CAS  Google Scholar 

  12. Greeff, C. W., Trinkle, D. R. & Albers, R. C. Shock-induced α–ω transition in titanium. J. Appl. Phys. 90, 2221–2226 (2001).

    Article  CAS  Google Scholar 

  13. Trinkle, D. R. et al. New mechanism for the α to ω martensitic transformation in pure titanium. Phys. Rev. Lett. 91, 025701 (2003).

  14. Trinkle, D. R. A Theoretical Study of the Hcp to Omega Martensitic Phase Transition in Titanium Thesis, Ohio State Univ. (2003).

    Google Scholar 

  15. Conrad, H. Effect of interstitial solutes on the strength and ductility of titanium. Prog. Mater. Sci. 26, 123–404 (1981).

    Article  CAS  Google Scholar 

  16. Hahn, T. (ed.) International Tables for Crystallography Vol. A. (Kluwer, Dordrecht, 1996).

    Google Scholar 

  17. Kutepov, A. L. & Kutepova, S. G. Crystal structures of Ti under high pressure: theory. Phys. Rev. B 67, 132102 (2003).

    Article  Google Scholar 

  18. Rudin, S. P., Jones, M. D. & Albers, R. C. Thermal stabilization of the hcp phase in titanium. Phys. Rev. B 69, 094117 (2004).

    Article  Google Scholar 

  19. Estrin, E. I. Concerning polymorphous (normal, martensitic) transformations. Fiz. Met. Metalloved. 37, 1249–1255 (1974).

    CAS  Google Scholar 

  20. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169–11186 (1996).

    Article  CAS  Google Scholar 

  21. Vanderbilt, D. Soft self-consistent pseudopotentials in a generalized eigenvalue formalism. Phys. Rev. B 41, 7892–7895 (1990).

    Article  CAS  Google Scholar 

  22. Kresse, G. & Hafner, J. Norm-conserving and ultrasoft pseudopotentials for first-row and transition elements. J. Phys. Condens. Matter 6, 8245–8257 (1994).

    Article  CAS  Google Scholar 

  23. Perdew, J. P. in Electronic Structure of Solids '91. (eds Ziesche, P. & Eschrig, H.) 11–20 (Akademie, Berlin, 1991).

    Google Scholar 

Download references

Acknowledgements

This research is supported by DOE Grants No. DE-FG02-99ER45795 (OSU) and No. W-7405-ENG-36 (LANL). Computational resources were provided by the Ohio Supercomputing Center, NERSC, and QSC at LANL. We thank G. T. Gray and M. Asta for helpful discussions.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Richard G. Hennig.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Hennig, R., Trinkle, D., Bouchet, J. et al. Impurities block the α to ω martensitic transformation in titanium. Nature Mater 4, 129–133 (2005). https://doi.org/10.1038/nmat1292

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nmat1292

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing