Hostname: page-component-8448b6f56d-tj2md Total loading time: 0 Render date: 2024-04-19T16:32:27.853Z Has data issue: false hasContentIssue false
  • English
  • Français

Strength, Ductility, and Fracture Mode of Ternary FeAl Alloys

Published online by Cambridge University Press:  22 February 2011

J. H. Schneibel ,
E. P. George ,
E. D. Specht  and
J. A. Horton
J. H. Schneibel
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831
E. P. George
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831
E. D. Specht
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831
J. A. Horton
Affiliation:
Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831
Get access

Abstract

Iron aluminides with the composition Fe-45Al-5X-0.2B-0.1Zr (at. %), where X stands for the first row transition metals Ti, V, Cr, Mn, Fe, Co, Ni, Cu, were examined at room temperature with respect to their strength, ductility, environmental sensitivity, and fracture mode. The extruded materials were annealed at 1273 K to produce similar grain sizes and subsequently at 673 K to reduce the amount of quenched in vacancies. All alloys were essentially single phase. Their solid solution strengthening was found to correlate with the atomic size misfit derived from the lattice parameters. The “binary” alloy Fe-45Al-0.2B-0.1Zr exhibited predominantly transgranular fracture. Ternary alloying additons with atomic numbers less than that of Fe tended to enhance intergranular fracture, whereas those with atomic numbers higher than that of Fe favored substantial amounts of transgranular fracture. Tensile testing in a partial pressure of dry oxygen increased the ductilities of the ternary alloys only slightly, whereas the ductility of the binary alloy increased from about 8 to about 19%. The ductilities in air correlated inversely with the yield strength. However, those alloys exhibiting substantial amounts of transgranular fracture always showed higher ductilities than those fracturing intergranularly. We interpret our fracture results in terms of yield strengths and ternary element site occupations.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 364: Symposium L – High-Temperature Ordered Intermetallic Alloys–VI , 1994 , 73
Copyright
Copyright © Materials Research Society 1995

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. Gypen, L. A. and Deruyttere, A., Scr. Metall. 15, 815 (1981).Google Scholar
2. Mishima, Y., Ochiai, S., Hamao, N., Yodagawa, M., and Suzuki, T., Trans. JIM 27, 648 (1986).Google Scholar
3. Kong, C. H. and Munroe, P. R., Scr. Metall. Mater. 30, 1079 (1994).Google Scholar
4. Kong, C. H. and Munroe, P. R., in Processing, Properties, and Applications of Iron Aluminides, Schneibel, J. H. and Crimp, M. A., eds., TMS, Warrendale, PA, 1994, pp. 231–239.Google Scholar
5. Fleischer, R. L., Acta Metall. 11, 203 (1963).Google Scholar
6. Li, D., Li, P., Sun, D., and Lin, D., in High-Temperature Ordered Intermetallic Alloys V, Baker, I., Darolia, R., Whittenberger, J. D., and Yoo, M. H., eds., Materials Research Society, Pittsburgh, Boston, 1993, vol. 288, pp. 281–286.Google Scholar
7. Fu, C. L. and Zou, J., these proceedings.Google Scholar
8. Khosla, S., Sparks, C. J., Schneibel, J., Specht, E. D., Jiang, X., Miller, M. K., Zschack, P., and McHargue, C. J., in Alloy Modeling and Design, Stocks, G. M. and Turchi, P. E. A., eds., TMS, Pittsburgh, 1994, pp. 257–65.Google Scholar
9. George, E. P., Yamaguchi, M., Kumar, K. S., and Liu, C. T., Annu. Rev. Mater. Sci. 24, 409 (1994).Google Scholar
10. Schneibel, J. H. and Specht, E. D., Scr. Metall. Mater. 31, 1737 (1994).Google Scholar