Hostname: page-component-5c6d5d7d68-ckgrl Total loading time: 0 Render date: 2024-09-02T06:14:38.935Z Has data issue: false hasContentIssue false
  • English
  • Français

Microstructural Characterization of α2 + γ Titanium Aluminides

Published online by Cambridge University Press:  02 July 2020

D. J. Larson  and
M. K. Miller
D. J. Larson
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6376
M. K. Miller
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831-6376
Get access

Extract

Two-phase α2+γ TiAl alloys with microalloying additions, Fig. 1, are of interest due to the high strength-to-weight ratio they can provide in automotive and aircraft applications. In boron-doped α2+γTiAl containing Cr, Nb, and W, the B levels were found to be significantly depleted below the nominal alloy content in both the α2 andγ phases. The boron solubilities in the γ and α2 phases were 0.011 ± 0.005 at. % B and 0.003 ± 0.005 at. % B, respectively in Ti-47% Al-2% Cr-1.8% Nb-0.2% W-0.15 % B that was aged for 2 h at 900°C (base alloy). The majority of the B was in a variety of borides including TiB, TiB2 and a Cr-enriched (Ti,Cr)2B precipitate. With the exception of the smaller (< 50 nm thick) Cr-enriched (Ti,Cr)2B precipitates, Fig. 2, most of the borides were larger than ∼100 nm. A significant proportion of the microalloying additions is in these borides, Table 1.

Type
Phase Transformations in Metals and Alloys
Information
Microscopy and Microanalysis , Volume 3 , Issue S2: Proceedings: Microscopy & Microanalysis '97, Microscopy Society of America 55th Annual Meeting, Microbeam Analysis Society 31st Annual Meeting, Histochemical Society 48th Annual Meeting, Cleveland, Ohio, August 10-14, 1997 , August 1997 , pp. 701 - 702
Copyright
Copyright © Microscopy Society of America 1997

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

1. Dimiduk, D. M., in Kim, Y-K.et al., Eds., Gamma Titanium Aluminides, Warrendale, PA: TMS (1995)21.Google Scholar

2. Liu, C. T.et al., Intermetallics 4 (1996) 429.CrossRefGoogle Scholar

3. Maziasz, P. J.et al., Intermetallics 5 (1997) 83.CrossRefGoogle Scholar

4. This research was sponsored by the Division of Materials Sciences, U. S. Department of Energy, under contract DE-AC05-96OR22464 with Lockheed Martin Energy Research Corp and was conducted utilizing the Shared Research Equipment (SHaRE) User Program facilities at Oak Ridge National Laboratory.Google Scholar