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Structure and mechanical properties of internally oxidized Ta-8 Pct W-2 Pct Hf (T-111) alloy

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Abstract

The deformation and fracture behavior of the Ta-8 wt pct W-2 wt pct Hf (T-111) alloy internally oxidized at 1273 K was studied at test temperatures up to 1589 K (2400°F). The results are discussed in terms of oxygen content, and the morphology of the oxide. Thermodynamic calculations based on lattice parameter measurements indicate that the oxygen solubility in T-111 is low, about 72 ppm at 1973 K. Beyond the solubility limit, oxygen reacts with hafnium to form hafnium oxide, which causes a continuous decrease in lattice parameter until all the hafnium has been removed from the solid solution. A homogeneous dispersion of fine, coherent hafnium-oxygen zones was observed in as-oxidized specimens. These zones coarsened upon annealing at or above 1673 K and eventually precipitated as rectangular HfO2 particles. Alteration of the oxygen distribution and oxide morphology by heat treatment resulted in large changes in the mechanical properties. For example, specimens aged 15 min at 1973 K showed little change up to 3500 ppm O, but above this level the yield strength increased and ductility decreased abruptly. Ductility was completely lost at 4200 ppm O, independent of test temperature. Specimens with no aging treatment other than oxygen addition lost all ductility at 800 ppm O. The structure and mechanical properties are correlated.

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References

  1. J. H. Swisher: “Internal Oxidation,” inOxidation of Metals and Alloys, pp. 235–67 ASM, Metals Park, Ohio, 1970.

    Google Scholar 

  2. G. S. Ansell, T. D. Cooper, and F. V. Lenel, eds.:Oxidation Dispersion Strengthening, Proceedings of a Symposium Held at Bolton Landing, N.Y., June 1966, Gordon and Breach, New York, 1968.

    Google Scholar 

  3. E. Orowan: inSymposium on Internal Stresses in Metals and Alloys, p. 451, Institute of Metals, London, 1948.

    Google Scholar 

  4. G. S. Ansell: “The Mechanism of Dispersion Strengthening: A Review,” inOxidation Dispersion Strengthening, Proceedings of a Symposium Held at Bolton Landing, N.Y., June 1966, pp. 61–141, Gordon and Breach, New York, 1968.

    Google Scholar 

  5. M. F. Ashby:Phil. Mag. 1966, vol. 14, p. 1157.

    Article  CAS  Google Scholar 

  6. E. N. Rhines, W. A. Johnson, and W. A. Anderson:Trans. AIME, 1942, vol. 147, p. 205.

    Google Scholar 

  7. E. Gregory and G. C. Smith:J. Inst. Metals, 1956–57, vol. 85, p. 81.

    CAS  Google Scholar 

  8. M. F. Ashby and R. M. A. Centamore:Acta Met., 1968, vol. 16, pp. 1081–92.

    Article  CAS  Google Scholar 

  9. D. M. Williams and G. C. Smith: “A Study of Oxide Particles and Oxide-Matrix Interface in Copper,” inOxidation Dispersion Strengthening, Proceedings of a Symposium Held at Bolton Landing, N. Y., June 1966, pp. 509–36, Gordon and Breach, New York, 1968.

    Google Scholar 

  10. R. M. Bonesteel, D. J. Rowcliffe, and T. E. Tietz:Trans. Japan Inst. Metals, 1968, vol. 9, suppl., p. 597.

    CAS  Google Scholar 

  11. S. A. Bradford:Trans. TMS-AIME, 1964, vol. 230, p. 1400.

    CAS  Google Scholar 

  12. H. Inoye:Contamination of Refractory Metals by Residual Gases in Vaccum Below 10 −6 Torr, ORNL-3674, September 1964.

  13. D. O. Hobson: “Aging Phenomena in Columbium-Base Alloys,” inHigh Temperature Materials, pp. 325–34, Interscience, New York, 1963.

    Google Scholar 

  14. J. R. Stewart, W. Lieberman, and G. H. Rowe: “Recovery and Recrystallization of Columbium-1.0% zirconium Alloy,” inColumbium Metallurgy, p. 407, Interscience, New York, 1960.

    Google Scholar 

  15. D. J. Rowcliffe, R. M. Bonesteel, and T. E. Tietz: “Strengthening of Niobium-Zirconium Alooys by Internal Oxidation,” inOxidation Dispersion Strengthening, Proceedings of Symposium Held at Bolton Landing, N. Y., June 1966, pp. 741–50, Gordon and Breach, New York, 1968.

    Google Scholar 

  16. J. B. Mitchell:Acta Met., 1971, vol. 19, p. 1063.

    Article  CAS  Google Scholar 

  17. L. Brewer:Chem. Rev., 1953, vol. 52, p. 1.

    Article  CAS  Google Scholar 

  18. D. R. Stoner:Determination of the Weldability and Elevated Temperature Stability of Refractory Metal Alloys, Final report, Task IV—The Effect of Contamination Level on the Weldability of Refractory Metal Alloys, WANLPR(P)-015, October 1969.

  19. D. E. Etter and W. H. Smith:J. Less-Common Metals, 1972, vol. 27, p. 109.

    Article  CAS  Google Scholar 

  20. H. Inouye: “Interactions of Refractory Metals with Active Gases in Vacua and Inert Gas Environments,” inRefractory Metal Alloys Metallurgy and Technology, I. Machlin, R. T. Begley, and E. D. Weisert, eds., pp. 165–95, Plenum Press, New York, 1968.

    Google Scholar 

  21. G. M. Wolten:J. Amer. Ceram. Soc., 1963, vol. 46, p. 418.

    Article  CAS  Google Scholar 

  22. C. T. Liu, H. Inouye, and R. W. Carpenter:J. Less-Common Metals, 1971, vol. 25, pp. 123–29.

    Article  CAS  Google Scholar 

  23. H. Braun and E. Rudy:Z. Metallk., 1960, vol. 51, p. 360.

    CAS  Google Scholar 

  24. R. W. Carpenter, C. T. Liu, and P. G. Marden:Met. Trans., 1971, vol. 2, pp. 125–31.

    CAS  Google Scholar 

  25. D. A. Vaughn, O. M. Stewart, and C. M. Schwartz:Trans. TMS-AIME, 1961, vol. 221, p. 937.

    Google Scholar 

  26. C. H. Schramm, P. Gordon, and A. R. Kaufmann:Trans. TMS-AIME, 1950, vol. 188, p. 196.

    Google Scholar 

  27. D. O. Hobson:Aging Phenomena in Columbium-Base Alloys, ORNL-3245, March 1962.

  28. R. W. Buckman and R. L. Ammon: Westinghouse Astronuclear Laboratory, Pittsburgh, personal communication, May 1972.

  29. R. W. Carpenter: “Transmission and Scanning Electron Microscope Observations of Niobium-Hafnium Alloys,” inElectron Microscopy and Structure of Materials, Proc. 5th Int. Materials Symp., Berkeley, Sept. 13–17, 1971, G. Thomas, R. M. Fulrath, and R. M. Fisher, eds., pp. 667–77, University of California Press, Berkeley, 1972.

    Google Scholar 

  30. P. N. T. Unwin and G. C. Smith:J. Inst. Metals, 1969, vol. 97, pp. 229–310.

    Google Scholar 

  31. K. D. Sheffler, J. C. Sawyer, and E. A. Steigerwald:Trans. ASM, 1969, vol. 62, p. 749.

    Google Scholar 

  32. D. Tabor:J. Inst. Metals, 1951, vol. 69, p. 1.

    Google Scholar 

  33. R. T. Begley, R. L. Ammon, and R. Stickler:Development of Niobium Base Alloys, WADC-TR-57-344, Part VI, February 1963.

  34. C. T. Liu and J. Gurland:Trans. ASM, 1968, vol. 61, pp. 156–67.

    CAS  Google Scholar 

  35. K. E. Puttick:Phil. Mag., 1959, vol. 4, p. 964.

    Article  CAS  Google Scholar 

  36. W. W. Platte:Welding J., 1963, vol. 42, pp. 69s-83s.

    CAS  Google Scholar 

  37. A. G. Ingram, M. W. Mallett, B. G. Koebe, E. S. Bartlett, and H. R. Ogden:Notch Sensitivity of Refractory Metals, ASD-TR-61-474, August 1961.

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This research was sponsored by the U.S. Atomic Energy Commission under contract with Union Carbide Corporation.

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Liu, C.T., Inouye, H. & Carpenter, R.W. Structure and mechanical properties of internally oxidized Ta-8 Pct W-2 Pct Hf (T-111) alloy. Metall Trans 4, 1839–1850 (1973). https://doi.org/10.1007/BF02665411

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