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Evolution of microstructure and phases in in situ processed Ti–TiB composites containing high volume fractions of TiB whiskers

Published online by Cambridge University Press:  31 January 2011

S. S. Sahay
Affiliation:
Department of Metallurgical Engineering, 135 South 1460 East Room 412, The University of Utah, Salt Lake City, Utah 84112
K. S. Ravichandran*
Affiliation:
Department of Metallurgical Engineering, 135 South 1460 East Room 412, The University of Utah, Salt Lake City, Utah 84112
R. Atri
Affiliation:
Department of Metallurgical Engineering, 135 South 1460 East Room 412, The University of Utah, Salt Lake City, Utah 84112
B. Chen
Affiliation:
Cercom Inc., 1960 Watson Way, Vista, California 97260
J. Rubin
Affiliation:
Cercom Inc., 1960 Watson Way, Vista, California 97260
*
b)Address all correspondence to this author.
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Abstract

A series of titanium composites, with varying volume fractions of titanium monoboride (TiB) whiskers, were made by mixing various proportions of titanium (Ti) and titanium diboride (TiB2) powders followed by hot pressing. The phases present were identified by x-ray diffraction. Microstructural examination revealed three different types of TiB whisker morphologies: (i) long and needle-shaped TiB whiskers that are isolated and randomly oriented in the Ti matrix at relatively low volume fractions (0.3), (ii) colonies of refined and densely packed TiB whiskers from intermediatevolume (0.55) to high volume (0.73 and 0.86) fractions, and (iii) coarse and elongated TiB particles with a few needle-shaped whiskers at the highest volume fraction (0.92). In all the composites, TiB was found to be the predominant reinforcement. However, in Ti–TiB composites with 0.86 and 0.92 volume fractions of TiB, a significant amount of TiB2 was also present. The relative volume fractions of Ti, TiB, and TiB2 phases were estimated from the integrated intensities of diffraction peaks by the direct comparison method employing the calculated structure factors and Lorentz polarization factors. The composite microstructure, as well as the evolution of different morphologies, of TiB whiskers is discussed.

Type
Articles
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1.Thompson, M.X. and Nardone, V.C., Mater. Sci. Eng. A144, 1221 (1991).Google Scholar
2.Crossman, F.W. and Yue, A.S., Metall. Trans. 1A, 1545 (1971).CrossRefGoogle Scholar
3.Valencia, J.J., Lofvander, J.P.A, McCullough, C., Levi, C.G., and Mehrabian, R., Mater. Sci. Eng. A144, 25 (1991).CrossRefGoogle Scholar
4.Binary Alloy Phase Diagram, ASM Handbook, edited by H. Baker (ASM International, Materials Park, OH, 1992), Vol. 3, p. 2.85.Google Scholar
5.Metcalfe, A.G., in Metal Matrix Composites, edited by Broutman, L.J. and Krock, R.H. (Academic Press, New York, 1974), Vol. 1, p. 65.Google Scholar
6.Fan, Z., Guo, Z.X., and Cantor, B., Composites 28A, 131 (1997).CrossRefGoogle Scholar
7.Atri, R., Ravichandran, K.S., and Jha, S.K., Acta Mater. (1998, in press).Google Scholar
8.De Graef, M., Lofvander, J.P.A, McCullough, C., and Levi, C.G., Acta Metall. Mater. 40, 3395 (1992).CrossRefGoogle Scholar
9.Graef, M. D., Lofvander, J.P.A, and Levi, C.G., Acta Metall. Mater. 39, 2381 (1991).CrossRefGoogle Scholar
10.Philliber, J.A., Dary, F.C., Zok, F.W., and Levi, C.G., in Recent Advances in Titanium Metal Matrix Composites, edited by Froes, F.H. and Storer, J. (The Minerals, Metals and Materials Society, Warrendale, PA, 1995), p. 213.Google Scholar
11.Philliber, J.A., Dary, F.C., Zok, F.W., and Levi, C.G., Titanium '95 Science and Technology, edited by Blenkinsop, P.A., Evans, W.J., and Flower, H.M. (The Institute of Materials, London, 1996), Vol. 3, p. 2714.Google Scholar
12.Wang, W.Y., Yi, H.C., and Petric, A., Metall. Mater. Trans. 29A, 3037 (1995).Google Scholar
13.Yamamoto, T., Otsuki, A., Ishihara, K., and Shingu, P.H., Mater. Sci. Eng. A239/240, 647 (1997).CrossRefGoogle Scholar
14.Li, D.X., Ping, D.H., Lu, Y.X., and Ye, H.Q., Mater. Lett. 16, 322 (1993).CrossRefGoogle Scholar
15.Saito, T., Takamiya, H., and Furata, T., in Titanium '95 Science and Technology, edited by Blenkinsop, P.A., Evans, W.J., and Flower, H.M. (The Institute of Materials, London, 1996), Vol. 3, p. 2859.Google Scholar
16.Hyman, M.E., McCullough, C., Valencia, J.J., Levi, C.G., and Mehrabian, R., Metall. Trans. 22A, 1647 (1991).CrossRefGoogle Scholar
17.Cullity, B.D., Elements of X-Ray Diffraction, 2nd ed. (Addison-Wesley, Reading, MA, 1978).Google Scholar
18.Spear, K.E., McDowell, P., and McMahon, F., J. Am. Ceram. Soc. 69, C4 (1986).CrossRefGoogle Scholar
19.Decker, B.F. and Kasper, R., Acta Crystallogr. 7, 77 (1954).CrossRefGoogle Scholar
20.McGeary, R.K., J. Am. Ceram. Soc. 44, 513 (1961).CrossRefGoogle Scholar
21.Milewski, J.V., in Proceedings of the 29th Annual Technical Conference (Reinforced Plastics/Composites Institute, The Society of Plastics Industry, Inc., Washington, DC, Section 10–B, 1974), p. 1.Google Scholar