Corrosion of metal matrix composites

Severe exfoliation has been reported with graphite/tJu-minum metal matrix composites in marine environments [5]. Localized corrosion along wire-wire and wire-foil diffusion bonds resulted in disbondment of the precursor wires and aluminum foils. See also the discussion by Hihara on corrosion of metal-matrix composites in Section VI of this manual. 

Opportunities for application of new materials as components in electrochemical cells (electrodes, electrolytes, membranes, and separators) are discussed in this section. In addition, electrochemical processing is considered in the sense that it presents opportunities for the synthesis of new materials such as electroepitaxial GaAs, graded alloys, and superlattices. Finally, attention is focused on the evolution of new engineering materials that were developed for reasons other than their electrochemical properties but that in some cases are remarkably inert (glassy alloys). Others that are susceptible to corrosion (some metal-matrix composites) and more traditional materials that are finding service in new applications (structural ceramics in aqueous media, for example) are also considered briefly. 

Rogne T, Solem T, Berget J. Effect of metallic matrix composition on the erosion corrosion behavior of WC-coatings. Proceedings of the United Thermal Spray conferance ASM Thermalspray Society, sept. 1997. 

Lin, S. Shih, H. Mansfeld, F. (1992). Corrosion Protection of Metal Matrix Composites by Polymer Coatings. Corrosion Science, Vol. 33, No. 9, pp. 1331-1349, ISSN 0010938X... 

Mansfeld, F., S. Lin and H. Shih, 1990a, Corrosion Protection of Metal Matrix Composites, Final Report for US Amy research Office, AD-A222 951 (University of Southern Caltforrtta). 

Aerosol spray delivery, 23 196 Aerosol sprays, 7 773-774 Aerospace applications aluminum alloys, 2 340 artificial graphite in, 72 740-741 for high performance fibers, 13 397-398 of liquid-crystal polymers, 20 85 metal-matrix composites in, 16 191 polyimide matrix composites in, 20 284 Aerospace bearings, corrosion resistance of, 74 452... 

Besides these developments, which are directed at specific applications, NijAl alloys are used for the development of inter-metallic matrix composites which contain reinforcing particles or fibers of borides, carbides, oxides or carbon (Fuchs, 1989 Lee et al., 1990 Tortorelli et al., 1990 Al-man and Stoloff, 1991 Kumar, 1991 McKamey and Carmichael, 1991 Muk-herjee and Khanra, 1991 Brennan etal., 1992). Apart from the mechanical properties and the necessary corrosion resistance, the chemical compatibility of the used phases is of primary importance with respect to the long-term stability. It was found that SiC, B4C, and TiBj react extensively with Nij Al alloys, whereas very little reaction has been observed with AljOj or Tie in NijAl (Fuchs, 1989 Lee etal., 1990 Brennan etal., 1992). It should be noted that NijAl alloys are used not only as the matrix material, but also as a reinforcing phase in, e.g. an Al alloy to form a metal-matrix composite (Metelnick and Varin, 1991). 

F. Mansfeld, S.L. Jeanpaquet, M.W. Kending, The evaluation of corrosion protection measures for metal matrix composites, Corros. Sci. 26 (1986) 727—734. 

Carbon fiber metal matrix composites are subject to corrosion, as is the unreinforced matrix [65], and must be provided with some form of surface protection. 

S] Turnbull, A., Review of Corrosion Studies on Aluminium Metal Matrix Composites," British Corrosion Journal, Vol. 27, No. 1, 1992, p. 27. 

JJ] Lucas, K. A. and Clarke, H., Corrosion of Aluminium-Based Metal Matrix Composites, Research Studies Press, England, John Wiley Sons, New York, 1993. 

Coleman, S. L., Scott, V. D., and McEnaney, B., Corrosion Behaviour of Aluminium-Based Metal Matrix Composites, Journal of Materials Science, Vol. 29, 1994, pp. 2826-2834. 

Shimizu, Y., Nishimura, T., and Matsushima, L, "Corrosion Resistance of Al-Based Metal Matrix Composites, Materials Science and Engineering A, Vol. 198, 1995, pp. 113-118. 

Dash, L. C., The Mechanism of Corrosion and Corrosion Control of Aluminum/Graphite Metal Matrix Composites, Ph.D. Thesis, Ohio State University, Columbus, OH, 1988. 

Nunes, P. C. R. and Ramanathan, L. V., Corrosion Behavior of Alumina-Aluminum and Silicon Carbide-Aluminum Metal-Matrix Composites, Corrosion, Vol. 51, No. 8,1995, pp. 610-617. 

Buarzaiga, M. M. and Thorpe, S. J., Corrosion Behavior of As-Cast, Silicon Carbide Particulate-Aluminum Alloy Metal-Matrix Composites, Corrosion, Vol. 50, No. 3, 1994, pp. 176-185. 

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