Oxidation and Protection of Ti3Al-Based Intermetallic Alloys

Abstract

Titanium aluminides containing 20–30 atom percent Al can suffer from severe subsurface embrittlement (alpha-case) when exposed to air at elevated temperatures for extended periods. For example.the alloys Ti-24Al-12.5Nb-1.5Mo and Ti-24Al-8Nb-2Mo-2Ta (based on the Ti3Al alpha-2 intermetallic compound) embrittle to a depth of about 80 microns during 1000 hours exposure to air at 815°C (1500°F), resulting in major reductions in tensile properties. Plasma-sprayed coatings of the MCrAlY and MCr types deposited over a thin diffusion barrier of chromium or tungsten, have been found effective in protecting these alloys against oxidation and embrittlement at this temperatures.

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References

  1. 1.

    H.A. Lipsett, MRS Symposium Proc., 39, 351 (1985).

    Article  Google Scholar 

  2. 2.

    M.F.X. Gigliotti and B.J. Marquardt, U.S.Patent 4,788,035, 1988.

  3. 3.

    J.W. Pickens and G.K. Watson, paper at 14th. Conf., on Metal Matrix, Carbon, and Ceramic Composites, Cocoa Beach, FL, Jan. 1990.

    Google Scholar 

  4. 4.

    Z. Liu and G. Welsch, Met. Trans. 19A, 1121 (1988).

    CAS  Article  Google Scholar 

  5. 5.

    S. Balsone in “Oxidation of High Temperature Intermetallics” (T. Grobstein and J. Doychak, Eds.) p.219, TMS, 1988.

  6. 6.

    D.W. McKee and K.L. Luthra, Surf. Coatings Tech., to be published.

  7. 7.

    D.W. McKee, paper at AeroMat ‘92 Conference, Anaheim, CA, May 1992.

    Google Scholar 

  8. 8.

    A. Barbuto and D.W. McKee, paper at IMS Conf., Monterey, CA, July 1991.

    Google Scholar 

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McKee, D.W. Oxidation and Protection of Ti3Al-Based Intermetallic Alloys. MRS Online Proceedings Library 288, 953–958 (1992). https://doi.org/10.1557/PROC-288-953

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