Hostname: page-component-586b7cd67f-t7fkt Total loading time: 0 Render date: 2024-11-29T07:34:02.078Z Has data issue: false hasContentIssue false
  • English
  • Français

Twinning in Crack Tip Plasticity of Two-Phase Titanium Aluminides

Published online by Cambridge University Press:  21 March 2011

Fritz Appel
Fritz Appel*
Affiliation:
Institute for Materials Research, GKSS Research Centre, Max-Planck-Straβe, D-21502 Geesthacht, GERMANY
Get access

Abstract

Intermetallic titanium aluminides based on γ(TiAl) are prone to cleavage fracture on low index lattice planes. Unfavourably oriented grains may therefore provide easy crack paths so that the cracks can rapidly grow to a length which is critical for failure. The effect of crack tip plasticity on crack propagation in γ(TiAl) was investigated by conventional and high-resolution electron microscopy. Crack tip shielding due to mechanical twinning was recognized as toughening mechanism, which occur at the atomic scale and apparently is capable to stabilize fastly growing cracks. The potential of the mechanism will be discussed in the context of novel design concepts for improving the strength properties of γ-base titanium aluminide alloys.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 646 , 2000 , N1.8.1
Copyright
Copyright © Materials Research Society 2001

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. Yoo, M.H., Fu, C.L., Lee, J.K., Twinning in Advanced Materials, Yoo, M.H., Wuttig, M. (Eds.), TMS, Warrendale, PA, 1994, p. 97.Google Scholar
2. Appel, F., Christoph, U., Wagner, R., Philos. Mag. A 72 (1995) 341.Google Scholar
3. Yoo, M.H. and Fu, C.L., Metall. Trans. A29 (1998) 49.Google Scholar
4. Chan, K.S., Metall. Trans. A24 (1993) 569.Google Scholar
5. Dimiduk, D.M., Gamma Titanium Aluminides, Kim, Y-W., Wagner, R., Yamaguchi, M. (Eds.), TMS, Warrendale, PA, 1995, 3.Google Scholar
6. Kim, Y-W., Dimiduk, D.M., Structural Intermetallics, Darolia, R., Liu, C.T., Martin, P.L., Miracle, D.B., Wagner, R., Yamaguchi, M. (Eds.), TMS, Warrendale, PA, 1997, p. 531.Google Scholar
7. Rice, J.R., Thomson, R., Philos. Mag. 29 (1974) 73.Google Scholar
8. Christian, J.W., Mahajan, S., Progress in Materials Science 39 (1995) 1.Google Scholar
9. Appel, F., Lorenz, U., Oehring, M., Sparka, U., Wagner, R., Mater. Sci. Eng. A233 (1997) 1.Google Scholar
10. Yamaguchi, M., Umakoshi, Y., Progress in Materials Science, 34 (1990) 1.Google Scholar
11. Appel, F., Wagner, R., Mater. Sci. Eng. R22 (1998) 187.Google Scholar
12. Appel, F., Oehring, M., Wagner, R., Novel Design Concepts for Gamma-Base Titanium Aluminides, Intermetallics, 2000, in print.Google Scholar
13. Appel, F., Lorenz, U., Paul, J.D.H., Oehring, M., Gamma Titanium Aluminides 1999, Kim, Y-W., Dimiduk, D.M., Loretto, M.H. (Eds.), TMS, Warrendale, PA, 1999, p. 381.Google Scholar
14. Christoph, U., Appel, F., Wagner, R., Mater. Sci. Eng. A 239–240 (1997) 39.Google Scholar