Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-18T08:32:24.412Z Has data issue: false hasContentIssue false

The Influence of Tungsten on the Chemical Composition of a Temporally Evolving Nanostructure of a Model Ni-Al-Cr Superalloy

Published online by Cambridge University Press:  01 June 2004

Chantal K. Sudbrack
Affiliation:
Department of Materials Science & Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208-3108, USA
Dieter Isheim
Affiliation:
Department of Materials Science & Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208-3108, USA
Ronald D. Noebe
Affiliation:
NASA Glenn Research Center, Cleveland, OH 44135, USA
Nathan S. Jacobson
Affiliation:
NASA Glenn Research Center, Cleveland, OH 44135, USA
David N. Seidman
Affiliation:
Department of Materials Science & Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208-3108, USA
Get access

Abstract

The influence of W on the temporal evolution of γ′ precipitation toward equilibrium in a model Ni-Al-Cr alloy is investigated by three-dimensional atom-probe (3DAP) microscopy and transmission electron microscopy (TEM). We report on the alloys Ni-10 Al-8.5 Cr (at.%) and Ni-10 Al-8.5 Cr-2 W (at.%), which were aged isothermally in the γ + γ′ two-phase field at 1073 K, for times ranging from 0.25 to 264 h. Spheroidal-shaped γ′ precipitates, 5–15 nm diameter, form during quenching from above the solvus temperature in both alloys at a high number density (∼1023 m−3). As γ′ precipitates grow with aging at 1073 K, a transition from spheriodal- to cuboidal-shaped precipitates is observed in both alloys. The elemental partitioning and spatially resolved concentration profiles across the γ′ precipitates are obtained as a function of aging time from three-dimensional atom-by-atom reconstructions. Proximity histogram concentration profiles (Hellman et al., 2000) of the quaternary alloy demonstrate that W concentration gradients exist in γ′ precipitates in the as-quenched and 0.25-h aging states, which disappear after 1 h of aging. The diffusion coefficient of W in γ′ is estimated to be 6.2 × 10−20 m2 s−1 at 1073 K. The W addition decreases the coarsening rate constant, and leads to stronger partitioning of Al to γ′ and Cr to γ.

Type
Research Article
Copyright
© 2004 Microscopy Society of America

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Amano, J. & Seidman, D.N. (1981). Range profiles of low-energy (100 to 1500 eV) implanted 3He and 4He atoms in tungsten. Phil Mag A 44, 177198.Google Scholar
Amano, J., Wagner, A., & Seidman, D.N. (1984). Diffusivity of 3He atoms in perfect tungsten crystals. J Appl Phys 56, 983992.Google Scholar
Ardell, A.J. & Nicholson, R.B. (1966). On modulated structure in aged Ni-Al alloys. Acta Met Mater 14, 12851309.Google Scholar
Blavette, D., Bostel, A., & Sarrau, J.M. (1985). Atom-probe microanalysis of a nickel-base superalloy. Met Trans A 16A, 17031711.Google Scholar
Blavette, D., Caron, P., & Khan, T. (1986). An atom-probe investigation of the role of rhenium additions in improving creep resistance of Ni-base superalloys. Scr Met Mater 20, 13951400.Google Scholar
Cerezo, A., Godfrey, T.J., Sijbrandij, S.J., Smith, G.D.W., & Warren, P.J. (1998). Performance of an energy-compensated three-dimensional atom-probe. Rev Sci Instr 68, 4958.Google Scholar
Copland, E.H., Jacobson, N.S., & Ritzert, F.J. (2001). Computational thermodynamic study to predict complex phase equilibria in the nickel-base superalloy René N6. NASA/TM, 210897.
Durand-Charre, M. (1997). The Microstructure of Superalloys. Amsterdam: Gordon and Breach Science.
Gleiter, H. & Hornbogen, E. (1967). Formation of coherent ordered precipitates in a Ni-Cr-Al-alloy. Z Metallk 58, 157163.Google Scholar
Gust, W., Hintz, H.B., Lodding, A., Odelius, H., & Predel, B. (1981). Impurity diffusion of Al in Ni single crystals studied by secondary ion mass spectrometry. Phys Status Solidi A 64, 187191.Google Scholar
Hellman, O.C., Blatz du Rivage, J., & Seidman, D.N. (2003). Efficient sampling for three dimensional atom probe microscopy data. Ultramicroscopy 95, 199205.Google Scholar
Hellman, O.C., Vandenbroucke, J.A., Blatz du Rivage, J., & Seidman, D.N. (2002). Application software for three-dimensional atom-probe data analysis. Mat Sci Eng A 327, 2933.Google Scholar
Hellman, O.C., Vandenbroucke, J.A., Rüsing, J., Isheim, D., & Seidman, D.N. (2000). Analysis of three-dimensional atom-probe data by the proximity histogram. Microsc Microanal 6, 437444.Google Scholar
Huang, W. & Chang, Y.A. (1999). A thermodynamic description of the Ni-Al-Cr-Re system. Mat Sci Eng A 259, 110119.Google Scholar
Hyde, J.M., Cerezo, A., Setna, R.P., Warren, P.J., & Smith, G.D.W. (1994). Lateral and depth scale calibration of the position sensitive atom-probe. Appl Surf Sci 76/77, 382391.Google Scholar
Jena, A.K. & Chaturvedi, M.C. (1984). The role of alloying elements in the design of nickel-base superalloys. J Mat Sci 19, 31213139.Google Scholar
Karunaratne, M.S.A., Carter, P., & Reed, R.C. (2000). Interdiffusion in the face-centered cubic phase of the Ni-Re, Ni-Ta and Ni-W systems between 900 and 1300°C. Mat Sci Eng A 281, 229233.Google Scholar
Kelly, P.M. (1982). Quantitative electron microscopy. Metals Forum 5, 1323.Google Scholar
Miller, M.K. (2000). Atom Probe Tomography. New York: Kluwer Academic.
Monma, K., Suto, H., & Oikawa, H. (1964). Diffusion of Ni63 and Cr51 in nickel-chromium alloys. J Jpn Inst Met 28, 188192.Google Scholar
Nathal, M.V. & Ebert, L.J. (1985). The influence of cobalt, tantalum, and tungsten on the microstructure of single crystal nickel-base superalloys. Met Trans A 16A, 18491862.Google Scholar
Pareige, C., Soisson, F., Martin, G., & Blavette, D. (1999). Ordering and phase separation in Ni-Cr-Al: Monte Carlo simulations vs. three-dimensional atom-probe. Acta Mater 47, 18891899.Google Scholar
Parratt, L.G. (1966). Probability and Experimental Errors in Science. New York: John Wiley and Sons.
Saunders, N. (2002). Ni-DATA v.4, Guildford, Surrey, UK: Thermotech Ltd.
Saunders, N. (1995). Phase-diagram calculations for high temperature structural materials. Philos T Roy Soc A 351, 543561.Google Scholar
Saunders, N. (1996). Phase-diagram calculations for Ni-based superalloys. In Superalloys 1996, Kissinger, J.D., Deye, D.J., Anton, D.L., Cetel, A.D., Nathal, M.V., Pollock, T.M. & Woodford, D.A. (Eds.), pp. 101110. Warrendale, PA: TMS.
Schmuck, C., Caron, P., Hauet, A., & Blavette, D. (1997). Ordering and precipitation of gamma′ phase in low supersaturated Ni-Cr-Al model alloy: An atomic scale investigation. Phil Mag A 76, 527542.Google Scholar
Schmuck, C., Danoix, F., Caron, P., Hauet, A., & Blavette, D. (1996). Atomic scale investigation of ordering and precipitation processes in a model Ni-Cr-Al alloy. Appl Surf Sci 94/5, 273279.Google Scholar
Sebastian, J.T., Hellman, O.C., & Seidman D.N. (2001). A new method for the calibration of three-dimensional atom-probe mass spectra. Rev Sci Instr 72, 29842988.Google Scholar
Sims, C.T. & Hagel, W.C. (1972). The Superalloys. New York: John Wiley & Sons.
Sudbrack, C.K., Yoon, K.Y., Mao, Z., Noebe, R.D., Isheim, D., & Seidman, D.N. (2003). Temporal evolution of nanostructures in a model nickel-base superalloy: Experiments and simulations. In Electron Microscopy: Its Role in Materials Science, Weertman, J.R., Fine, M.E., Faber, K.T., King, W. & Liaw, P. (Eds.), pp. 4350. Warrendale, PA: TMS.
Sundman, B., Jansson, B., & Andersson, J.-O. (1985). Calphad-computer coupling of phase diagrams and thermochemistry. CALPHAD 9, 153190.Google Scholar
van Bakel, G.P.E.M., Hariharan, K., & Seidman, D.N. (1995). On the structure and chemistry of Ni3Al on an atomic scale via atom-probe field-ion microscopy. Appl Surf Sci 90, 95105.Google Scholar
Wagner, A. & Seidman, D.N. (1979). Range profiles of 300- and 475-eV 4He+ ions and the diffusivity of 4He in tungsten. Phys Rev Lett 42, 515518.Google Scholar
Warren, P.J., Cerezo, A., & Smith, G.D.W. (1998). An atom-probe study of the distribution of rhenium in a nickel-based superalloy. Mat Sci Eng A 250, 8892.Google Scholar
Yamamoto, M. & Seidman, D.N. (1983). The quantitative compositional analysis and field-evaporation behavior of ordered Ni4Mo on an atomic plane-by-plane basis: An atom-probe field-ion microscope study. Surf Sci 129, 281300.Google Scholar