Paper Titles
Asymmetric Rolling as Means of Texture and Ridging Control and Grain Refinement of Aluminum Alloy and Steel Sheets
p.1
High Performance Materials Development in the 21st Century: Trends and Directions
p.7
Toughness Assessment of a Variety of Materials: Similarities and Discrepancies
p.13
Modeling Precipitate Microstructure Evolution in Alloys with First-Principles Energetic Information
p.19
Processing and Alloy Development to Optimise the Properties and Cost-Effectiveness of Components Manufactured from TiAl-Based Alloys
p.25
Orientation Dependence of Dynamic Recrystallization Behavior of Al Single Crystals
p.31
Recent Progress in Molecular Orbital Approach to Alloy Design
p.37
Aerosol Deposition Method for Fabrication of Nano Crystal Ceramic Layer
p.43
Quantitative Analysis of Precipitation Behavior in Ferrite of V Added Microalloyed Steel
p.49

Processing and Alloy Development to Optimise the Properties and Cost-Effectiveness of Components Manufactured from TiAl-Based Alloys

Article Preview

Abstract:

The IRC has carried out a major research programme over the last ten or so years aimed at developing the processing and optimisation of TiAl-based alloys. This work has covered melting, the production of shaped castings, powder processing and a range of thermomechanical processing routes in parallel with alloy development. In this paper the work aimed at understanding the factors that influence the properties of thermo-mechanically processed and cast samples of TiAl-based alloys will be reviewed. It is shown that the use of boron to control the grain size of castings leads to limited ductility in the stronger and more highly alloyed TiAl alloys because ribbon-like borides up to 200µm in length can be formed. It is also shown that although a fully lamellar microstructure offers a good balance of properties their plastic anisotropy leads to pre-yield fracture and to reduced fatigue life. It is clear that grain size control is essential if an acceptable balance of properties is to be obtained but that if casting is to be used grain refinement via boron addition is not totally satisfactory. A simple heat treatment can be used to refine the microstructure of cast boron-free alloys, which leads to ductility comparable with that in wrought samples and the associated convoluted microstructure should also eliminate pre-yield cracking.

You might also be interested in these eBooks
Designing, Processing and Properties of Advanced Engineering Materials View Preview

Info:

Periodical:

Materials Science Forum (Volumes 449-452)

Pages:

25-30

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.449-452.25

Citation:

Cite this paper

Online since:

March 2004

Authors:

Xin Hua Wu, D. Hu, M.H. Loretto

Keywords:

Fracture, Grain Size, Microstructure, Phase Transformation, TiAl Alloys

Export:

RIS, BibTeX

Price:

Permissions CCC:

Request Permissions

Permissions PLS:

Request Permissions

Сopyright:

© 2004 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

References

[1] Y Kim and DM Dimiduk 1991 JOM 43 (8) 40.

Google Scholar

[2] D M Dimiduk 1999 Mat Science and Engineering A263 281.

Google Scholar

[3] B Godfrey, A L Dowson and M H Loretto 1995 Gamma titanium aluminides (TMS Warrendale) Eds Y W Kim, R Wagner and M Yamaguchi] 467.

Google Scholar

[4] B J Inkson, C B Boothroyd and C J Humphreys 1993 J de Physique 1V 397.

Google Scholar

[5] D Hu 2003 Intermetallics 10, 851.

Google Scholar

[6] T T Cheng 1999 Intermetallics 8 29.

Google Scholar

[7] A B Godfrey PhD thesis 1996 The University of Birmingham.

Google Scholar

[8] A Denquin, S Naka and T Khan Proc Ti 92 Science and Technology (Froes and Caplan) Warrendale Pennsylvania TMS. p.1017.

Google Scholar

[9] X D Zhang, S Godfrey, M Weaver, M Strangwood, P Threadgill, M J Kaufman, and M H Loretto Acta materia 1996 44, 3723.

DOI: 10.1016/1359-6454(95)00453-x

Google Scholar

[10] D Hu and R R Botten, Intermetallics 2002, v10 (7), 701.

Google Scholar

[11] A B Godfrey, D Hu and M H Loretto Phil Mag A 1998 77(20) 287.

Google Scholar

[12] J M K Wiezorek, X D Zhang, A B Godfrey, D Hu, M H Loretto and H L Fraser. Scripta mater 1998 38(5) 811.

Google Scholar

[13] R Botten, Xinhua Wu, D Hu and M H Loretto Acta materia 2001, 49, 1687.

Google Scholar

[14] Xinhua Wu, D Hu, R Botten and M H Loretto, Acta materia 2001, 49, 1693.

Google Scholar

[15] Xinhua Wu, D Hu, M Preuss, P Withers and M H Loretto (to be published).

Google Scholar

[16] H Inui, A Nakamura, M H Oh and M Yamaguchi Acta materia, 1992, 40, 3095.

Google Scholar

[17] A B Godfrey, D Hu and M H Loretto 1997 Proc Intnl Symposium on designing, processing and properties of advanced engineering materials. Toyahashi Japan 37.

Google Scholar

[18] M Morris Intermetallics 1997 5(5) 327.

Google Scholar

[19] F Appel (private communication).

Google Scholar