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Low Temperature Superplasticity of Submicrocrystalline Titanium Alloys

Trans Tech Publications Ltd
Materials Science Forum
Authors:
Gennady Salishchev at Belgorod National Research University
Gennady Salishchev
Rafail Galeyev at Institute for Metals Superplasticity Problems of Russian Academy of Sciences
Rafail Galeyev
S.P. Malisheva
S.P. Malisheva
S.P. Malisheva
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Oleg R. Valiakhmetov
Oleg R. Valiakhmetov
Oleg R. Valiakhmetov
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Abstract

Severe plastic deformation at temperatures below 0.4...0.5Tm was used to obtain submicrocrystalline (SMC) structure in pure titanium and titanium alloys Ti-6.7Al-4.7Mo and Ti-11Mo-5.5Sn-4.2Zr. The structural studies showed that the density of titanium and its alloys in the SMC condition was less that in the coarse grained (CG) one. This change is connected with the presence of less-density intercrystalline regions. Low temperature superplasticity was studied in the temperature range 450...575°C. A considerable dependence of ductility on alloy composition was shown. The calculated value of apparent activation energy of the Ti-6.7Al-4.7Mo was equal to 315 kJ/mol at n=2.3, that being higher than during superplastic (SP) deformation of the alloy with usual microstructure.
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Materials Science Forum Vols. 243-245 (1997) pp 585-590
online at http://www.scientific.net
© (1997) Trans Tech Publications, Switzerland
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publisher: Trans Tech Publications Ltd, Switzerland, www.ttp.net. (ID: 212.193.134.82-15/12/08,13:07:52)
2 Superplasticity in Advanced Materials - ICSAM-97
Materials Science Forum Vols. 243-245 3
4 Superplasticity in Advanced Materials - ICSAM-97
Materials Science Forum Vols. 243-245 5
6 Superplasticity in Advanced Materials - ICSAM-97
Superplasticity in Advanced Materials - ICSAM-97
doi:10.4028/0-87849-759-5
Low Temperature Superplasticity of Submicrocrystalline Titanium Alloys
doi:10.4028/0-87849-759-5.585
Materials Science Forum Vols. 243-245 7
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