Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-24T09:03:03.880Z Has data issue: false hasContentIssue false
  • English
  • Français

Phase Equilibria Among β/α/α2/γ Phases and Phase Transformations in Ti-Al-Cr System at Elevated Temperatures

Published online by Cambridge University Press:  12 February 2019

Ali Shaaban Open the ORCID record for Ali Shaaban [Opens in a new window] ,
Hideki Wakabayashi ,
Hirotoyo Nakashima  and
Masao Takeyama
Ali Shaaban*
Affiliation:
School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan Surface Protection and Corrosion Control Lab., Central Metallurgical Research and Development Institute (CMRDI), EGYPT
Hideki Wakabayashi
Affiliation:
School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
Hirotoyo Nakashima
Affiliation:
School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
Masao Takeyama
Affiliation:
School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
*
*(Email: [email protected])
Get access

Abstract:

Effects of Cr addition to TiAl alloy on the phase equilibria among β/α/α2/γ Phases and phase transformation pathways within the temperature range of 1523 K∼1073 K were investigated using several alloys in the composition of interest. In between 1473 K and 1373 K, The slope of β/α tie-line in the three-phase coexisting region of β+α+γ remains basically unchanged. However, this slope drastically rotates in a clockwise direction, in between 1373 K and 1273 K and below the eutectoid reaction temperature in the binary system (1400 K). This is a strong indication that α-phase exists even below the 1400 K, i.e. addition of Cr stabilizes α against α2 and the three-phase coexisting region of β+α2+γ at lower temperatures is formed through a ternary eutectoid reaction (α → β+α2+γ) with decreasing temperature. This three-phase tie-triangle moves towards lower Al content in phase diagram. This suggests that Cr addition results in increase of the volume fraction of γ-phase with decreasing temperature even in alloys with low Al content.

Keywords

phase equilibriaphase transformation
Type
Articles
Information
MRS Advances , Volume 4 , Issue 25-26: Processing and Manufacturing , 2019 , pp. 1471 - 1476
Check for updates
Copyright
Copyright © Materials Research Society 2019 

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

Takeyama, M., Kobayashi, S., Intermetallics 13, 993 (2005)10.1016/j.intermet.2004.12.014CrossRefGoogle Scholar
Takeyama, M., Kato, Y., Kikuchi, M. in Titanium 95, Science and Technology, edited by Blenkinsop, P. A., Evanie, W. J. and Filower, H. M., (The Institute of Metals, London, 1996) p. 294Google Scholar
Nakamura, H., Takeyama, M., Wei, L., Yamabe, Y., Kikuchi, M., edited by Yamaguchi, M. and Fukutomi, H., (3rd Jpn Int. SAMPE Symp. Proc. 1993) p. 1353Google Scholar
Nakamura, H., Takeyama, M., Yamabe, Y., Kikuchi, M. Scripta Metall. 28, 997 (1993)CrossRefGoogle Scholar
Takeyama, M., Kikuchi, M. Mater Jpn. 35, 1058 (1996)10.2320/materia.35.1058CrossRefGoogle Scholar
Takeyama, M., Ohmura, Y., Kikuchi, M., Matsuo, T. Intermetallics 6, 643 (1998)10.1016/S0966-9795(98)00049-1CrossRefGoogle Scholar
Kobayashi, S., PhD Thesis, Tokyo Institute of Technology, 2001Google Scholar
Kobayashi, S., Takeyama, M.,Motegi, T., Hirota, N. ,Matsuo, T. in Gamma titanium aluminides 2003, edited by Kim, Y. –W, Clemens, H., Rosenberger, A. H., (Met. Mat. Soc. Symp.Proc.,Warrendale, PA, 2003) p. 165Google Scholar
Kobayashi, S., Takeyama, M., Matsuo, T., Kikuchi, M., edited by Imam, M.A., DeNale, R., Hanada, S., Zhong, Z. and Lee, D.N., (3rd PRICM3 Symp. Proc.TMS, Honolulu, 1998) p.2373Google Scholar
Petzow, G., Effenberg, G., Ternary Alloys 4, 3rd edn. VHC, Verlagsgesellschaft, Stuttgart, 1993) p. 433Google Scholar