Abstract
The 1200°C and 1300°C isothermal and cyclic oxidation behavior of Al2O3 continuous fiber (Saphikon™)-reinforced/ NiAl composites were studied. Oxidation resulted in formation of Al2O3 external scales in a similar manner as scales formed on monolithic NiAl. The isothermal oxidation of an Al2O3/NiAl composite resulted in oxidation of the matrix along the fiber/matrix interface near the fiber ends. This oxide acted as a wedge between the fiber and matrix, and, under cyclic oxidation conditions, led to further oxidation along the fiber lengths and eventual cracking of the composite. The oxidation behavior of composites in which the Al2O3 fibers were sputter coated with nickel prior to processing was much more severe. This was attributed to open channels around the fibers which formed during processing most likely as a result of the diffusion of the nickel coating into the matrix.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R. H. Singleton, A. V. Wallace, and D. G. Miller, Summary of the Eleventh Refractory Composites Working Group Meeting, AFML-TR-66-170 (1966), p. 717.
R. Darolia,J. Met. 43, 44 (1991).
R. D. Noebe, R. R. Bowman, C. L. Cullers, and S. V. Raj, NASACP-10051 (1990), pp. 20–21.
S. Reuss and H. Vehoff,Scripta Metall. Mater. 24, 1021 (1990).
R. D. Noebe, R. R. Bowman, and J. I. Eldridge, Initial evaluation of continuous fiber reinforced NiAl composites, Mater. Res. Soc. Pro.,194, inIntermetallic Matrix Composites, D. Miracle and P. Martin, eds. (Materials Research Society, Pittsburgh, Pennsylvania, 1990), pp. 323–331.
G. C. Rybicki and J. L. Smialek, Effect of theθ toα-Al2O3 transformation on the oxidation behavior ofβ-NiAl+Zr,Oxid. Met. 31, 275–304 (1989).
C. A. Barrett, The effect of 0.1 atomic percent zirconium level on the cyclic oxidation resistance of β-NiAl,Oxid. Met. 30, 361–390 (1988).
J. Doychak, J. L. Smialek, and C. A. Barrett, The oxidation of Ni-rich Ni-Al intermetallics, inOxidation of High Temperature Intermetallics, T. Grobstein and J. Doychak, eds. (TMS, Warrendale, Pennsylvania, 1988), pp. 41–57.
J. Doychak, C. A. Barrett, and J. L. Smialek, Oxidation between 1000°C and 1600°C and limiting criteria for the use of Zr-dopedβ-NiAl andβ/γ alloys, inCorrosion and Particle Erosion at High Temperatures, V. Srinivasan and K. Vedula, eds. (TMS, Warrendale, Pennsylvania, 1989), pp. 487–514.
J. A. Nesbitt, C. A. Barrett, J. Doychak, and E. J. Vinarcik, Oxidation and Diffusional Transport inβ-NiAl-X Alloys, NASA CP 10051 (1990), pp. 18–81.
J. W. Pickens, R. D. Noebe, G. K. Watson, P. K. Brindley, and S. L. Draper, Fabrication of Intermetallic Matrix Composites by the Powder Cloth Process, NASA TM 102060 (1989).
J. Doychak, C. A. Barrett, Unpublished research, NASA Lewis Research Center, Cleveland, Ohio (1990).
J. Doychak, J. L. Smialek, and T. E. Mitchell, Transient oxidation of single-crystalβ-NiAl,Met. Trans. A 20A, 499–518 (1989).
D. A. Voss, E. P. Butler, and T. E. Mitchell, The growth of hematite blades during the high temperature oxidation of iron,Met. Trans. A 13A, 929–935 (1982).
J. Doychak and M. Rühle, TEM studies of oxidized NiAl and Ni3Al cross section,Oxid. Met. 31, 431–452 (1989).
J. L. Smialek, Effects of diffusion on aluminum depletion and degradation of NiAl coatings,J. Electrochem. Soc. 121, 800–805 (1974).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Doychak, J., Nesbitt, J.A., Noebe, R.D. et al. Oxidation of A12O3 continuous fiber-reinforced/NiAl composites. Oxid Met 38, 45–72 (1992). https://doi.org/10.1007/BF00665044
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00665044