Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-20T01:01:45.263Z Has data issue: false hasContentIssue false
  • English
  • Français

Oxygen induced chemical ordering and ultrafine lamellar structure formation in a Ti-48 at. % Al alloy

Published online by Cambridge University Press:  11 February 2011

Williams Lefebvre ,
Annick Loiseau  and
Alain Menand
Williams Lefebvre
Affiliation:
Groupe de Physique des Materiaux, UMR CNRS 6634, Institut des Matériaux de Rouen, UFR, Sciences et Techniques, Technopôle du Madrillet, 76801 Saint Etienne du Rouvray, FRANCE
Annick Loiseau
Affiliation:
Laboratoire d'Etude des Microstructures, UMR CNRS-ONERA, ONERA, BP 72, 29 av. de la Division Leclerc, 92322 Châtillon, FRANCE
Alain Menand
Affiliation:
Groupe de Physique des Materiaux, UMR CNRS 6634, Institut des Matériaux de Rouen, UFR, Sciences et Techniques, Technopôle du Madrillet, 76801 Saint Etienne du Rouvray, FRANCE
Get access

Abstract

Influence of oxygen on the microstructure development of a Ti-48 at. % Al alloy has been investigated by means of transmission electron microscopy and 1D atom probe. Oxygen is found to significantly increase the temperature of the α → α2 chemical ordering reaction. As a consequence, above a critical oxygen content, the α → α2 transformation is substituted to the α → γm massive transformation when the Ti-48 Al alloy is quenched from the single a-phase field. In such a case, our pervious work has shown that the alloy exhibits a fully (α2 + γ) ultrafine lamellar structure. The present work gives a complete description of the ultrafine lamellar structure formation which, in opposition to the classical lamellar structure formation, involves an intragranular nucleation and growth of the γ phase within the α2 matrix.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 753: Symposium BB – Defect Properties and Related Phenomena in Intermetallic Alloys , 2002 , BB3.6
Copyright
Copyright © Materials Research Society 2003

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. Kawabata, T., Tadano, T. and Izumi, O., Scripta metall. 22, 1725 (1988).Google Scholar
2. Huang, S.C. and Siemers, P.A., Met. Trans. A 20A, 1899 (1989).Google Scholar
3. Vasudevan, V.K., Stucke, M.A., Court, S.A. and Fraser, H.L., Phil. Mag. Lett. 59, 299 (1989).Google Scholar
4. Kad, B.K. and Fraser, H.L., Phil. Mag. Lett. 70, 211 (1994).Google Scholar
5. Menand, A., Huguet, A. and Nérac-Partaic, A., Acta mater. 44, 4729 (1996).Google Scholar
6. Takagi, S. and Ouchi, C., Mater. Trans. JIM, 38, 285 (1997).Google Scholar
7. Perdrix, F., Trichet, M.-F., Bonnentien, J.-L., Cornet, M. and Bigot, J., Euromat, Edited by Morris, D.G., Naka, S., and Caron, P., 289 (1999).Google Scholar
8. Lefebvre, W., Loiseau, A., Thomas, M. and Menand, A., Phil. Mag. A 82, 2341–2355 (2002).Google Scholar
9. Sarrau, J.M., Danoix, F., Deconihout, B., B., , Bouet, M., Menand, A. and Blavette, D., App. Surf. Sci. 76/77, 367–373 (1993).Google Scholar
10. McCullough, C., Valencia, J.J., Levi, C.G. and Mehrabian, R., Acta Met. 37, 1321 (1989).Google Scholar
11. Veeraraghavan, D., Wang, P. and Vasudevan, V.K., Acta mater. 47, 3313–3330 (1999).Google Scholar
12. Denquin, A. and Naka, S., Acta metall. 44, 343 (1996).Google Scholar
13. Singh, S.R. and Howe, J.M., Phil. Mag. A 66, 739 (1992).Google Scholar
14. Qin, G.W., Hao, S. and Sun, X., Scripta metall. 39, 289 (1998).Google Scholar