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Zirconia and organotitanate film formation on graphite fiber reinforcement for metal matrix composites

Published online by Cambridge University Press:  31 January 2011

R.V. Subramanian
Affiliation:
Department of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164-2920
Eric A. Nyberg*
Affiliation:
Department of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164-2920
*
a)Present address: Ris⊘ National Laboratory, DK4000 Roskildle, Denmark.
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Abstract

The formation and characterization of zirconia coatings on graphite/carbon filaments were investigated. The objective was to eliminate or minimize degradative chemical reactions and improve bonding at the metal/carbon-fiber interface when the coated fiber is used as reinforcement in metal matrix composites. Thin, homogeneous films of zirconium oxide, ZrO2, less than 1μm thick, were formed on carbon monofilaments (35 μm diameter) from a zirconium oxychloride solution in water (less than 1.0 wt. % ZrO2) by dip coating and heating. Chemical changes during thermal decomposition and polycondensation were examined by FTIR spectroscopy. Through dynamic x-ray diffraction tests, the zirconia coating was found to transform first to a metastable tetragonal phase on heating to 330 °C, and then upon cooling, to a stable monoclinic structure. Organotitanate coatings were formed by electrodeposition of the ionizable organometallic complex, titanium di(dioctylpyrophosphate) oxyacetate (TDPA). Single fiber tests revealed a slight reduction in the strength of fibers with thicker coatings, probably due to crack initiation by brittle fracture of the ZrO2 coating. Thin coatings applied from 0.25% ZrOCl2 did not cause such strength reduction. Effective bonding of ZrO2 coatings to the filaments was revealed in single filament composite tests which showed the interfacial shear strength (IFSS) of the coated filaments in an epoxy matrix to be higher than that of the uncoated filaments. The IFSS of monofilaments electrocoated by the titanate was also higher. Examination of the fracture surfaces showed fiber pull-out associated with poor bonding in the case of specimens prepared from uncoated monofilaments. The coated monofilaments showed no fiber pull-out, suggesting that maximum fiber strength was achieved and transferred through the interface to the matrix. Finally, the chemical and thermal stability of the interfacial region of coated and uncoated graphite rods embedded in an aluminum matrix were evaluated. The uncoated rod showed little or no interfacial bonding to the metal matrix, suggesting poor wetting, while the dip-coated and electrocoated rods showed good wetting and compatibility with the metal matrix.

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Articles
Copyright
Copyright © Materials Research Society 1992

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References

1.Metcalfe, A. G. and Klein, M. J., Composite Materials (Academic Press, New York and London, 1974), Vol. 1, p. 13.Google Scholar
2.Ochiai, S. and Osamura, K., Metall. Trans. A 18A, 673 (1987).CrossRefGoogle Scholar
3.Ochiai, S. and Osamura, K., J. Mater. Sci. 23, 886 (1988).CrossRefGoogle Scholar
4.Crasto, A. S., Own, S. H., and Subramanian, R. V., Polym. Composites 9, 79 (1988).CrossRefGoogle Scholar
5.Taehwan Jung, “Preparation and characterization of hydrolyzed zirconia film on graphite fiber by the sol-gel process,” M.S. Thesis, Washington State University (1988).Google Scholar
6.Subramanian, R. V. and Velpari, V., “Strength and Durability of Basalt Fibers,” paper presented at the Pan Pacific Congress in Ceramics, Am. Ceram. Soc., Seattle, WA, October 2224 (1986).Google Scholar
7.Nyberg, Eric, “Characterization and Evaluation of Oxide Coatings on Carbon Fibers for Use in Metal Matrix Composites,” M.S. Thesis, Washington State University (1989).Google Scholar
8.Subramanian, R. V. and Jakubowski, J. J., Composites 11, 161 (1980).Google Scholar
9.Katzman, H., J. Mater. Sci. 22, 144 (1987).CrossRefGoogle Scholar
10. Joint Committee on Powder Diffraction Standards (1976).Google Scholar
11.Mazdiyasni, K. S., Lynch, C. T., and Smith, J. S., J. Am. Ceram. Soc. 48, 372 (1965).CrossRefGoogle Scholar
12.Clearfield, A., Rev. Pure Appl. Chem. 14, 91 (1964).Google Scholar
13.Jutson, J. A., Richardson, R. M., Jones, S. L., and Norman, C., in Better Ceramics Through Chemistry IV, edited by Zelinski, B. J. J., Brinker, C. J., Clark, D. E., and Ulrich, D. R. (Mater. Res. Soc. Symp. Proc. 180, Pittsburgh, PA, 1990).Google Scholar
14.Powers, D. A. and Gray, H. B., Inorg. Chem. 12, 2721 (1973).CrossRefGoogle Scholar
15.Aveston, J., Cooper, G. A., and Kelly, A., The properties of fibre composites, NPL Conference Proceedings, 4 November 1971 (IPC Science and Technology Press Ltd., 1971), pp. 1526.Google Scholar
16.Own, S. H., Subramanian, R. V., and Saunders, S. C., J. Mater. Sci. 21, 3912 (1986).CrossRefGoogle Scholar
17.Ueki, M., Naka, M., and Okamoto, I., J. Mater. Sci. 23, 2983 (1988).CrossRefGoogle Scholar
18.Maruyama, B. and Rabenberg, L., Interfaces in Metal-Matrix Composites, edited by Dhingra, A. K. and Fishman, S. G. (ASM, Metals Park, OH, 1986), p. 233.Google Scholar
19.Izumi, K., Murakami, M., Deguchi, T., and Morita, A., J. Am. Ceram. Soc. 72, 1465 (1989).CrossRefGoogle Scholar