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Phase Equilibria Effects on the Enhanced Liquid Phase Sintering of Tungsten-Copper

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Abstract

The sintering behavior and mechanical properties of W-Cu are improved by the addition of elements that have solubility for W,e.g., Co, Ni, Fe, and Pd. The degree of enhancement with small concentrations of additive is dependent on specific phase diagram features, and the ranking of effectiveness does not follow the trend observed for the activated solid-state sintering of W. These observations are explained through a combination of liquid phase sintering and activated sintering theories that considers the combined W, Cu, and activator phase equilibria effects. In small concentrations, Ni and Pd have little effect on densification because they go into solution with Cu, resulting in only a slight increase in the solubility of W in the liquid phase. In this case, the sintered density, strength, and hardness increase with increasing additive concentration due to enhanced densification through solution-reprecipitation. Cobalt and Fe are the most ef-fective activators due to their limited solubility in Cu and the formation of a stable intermetallic phase with W at the sintering temperature. This promotes the formation of a high-diffusivity interboundary layer which enhances solid-state sintering of the tungsten grains at temperatures at which a liquid phase is present. With Co and Fe additions, the sintered density, strength, and hardness peak with activator concentrations of 0.35 to 0.5 wt pct. An evaluation of models for activated solid-state sintering and liquid phase sintering indicates a substantial solid-state contribution to densification when a high-diffusivity interboundary layer is present and the sol-ubility of W in the liquid phase is small.

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References

  1. G.H.S. Price, C.J. Smithells, and S.V. Williams:J. Inst. Met., 1938, vol. 62, pp. 239–64.

    Google Scholar 

  2. G.H. Gessinger and K.N. Melton:Powder Metall. Int., 1977, vol. 9, pp. 67–72.

    CAS  Google Scholar 

  3. J. Vacek:Planseeberichte fur Pulvermetallurgie, 1959, vol. 7, pp. 6–17.

    CAS  Google Scholar 

  4. H.W. Hayden and J.H. Brophy:J. Electrochem. Soc, 1963, vol. 110, pp. 805–10.

    Article  CAS  Google Scholar 

  5. J.H. Brophy, H.W. Hayden, and J. Wulff:Trans. TMS-AIME, 1961, vol. 221, pp. 1225–31.

    CAS  Google Scholar 

  6. R.M. German and Z.A. Munir:High Temp. Sci., 1976, vol. 8, pp. 267–80.

    CAS  Google Scholar 

  7. R.M. German and V. Ham:Int. J. Powder Metall. Powder Technol., 1976, vol. 12, pp. 115–25.

    CAS  Google Scholar 

  8. R.M. German and Z.A. Munir:Metall. Trans. A., 1976, vol. 7A, pp. 1873–77.

    Article  CAS  Google Scholar 

  9. C.J. Li and R.M. German:Metall. Trans. A, 1983, vol. 14A, pp. 2031–41.

    Article  CAS  Google Scholar 

  10. C.J. Li and R.M. German:Int. J. Powder Metall. Powder Technol., 1984, vol. 20, pp. 149–62.

    CAS  Google Scholar 

  11. Z.A. Munir and R.M. German:High Temp. Sci., 1977, vol. 9, pp. 275–83.

    CAS  Google Scholar 

  12. G. Petzow, W.A. Kaysser, and M. Amtenbrink:Sintering-Theory and Practice, D. Kolar, S. Pejovnik, and M.M. Ristic, eds., Elsevier, Amsterdam, 1982, pp. 27–36.

    Google Scholar 

  13. P.E. Zovas, R.M. German, K.S. Hwang, and C.J. Li:J. Met., 1983, vol. 35 (1), pp. 28–33.

    Google Scholar 

  14. G. Petzow, W.A. Kaysser, and M. Amtenbrink:Sintering-Theory and Practice, D. Kolar, S. Pejovnik, and M.M. Ristic, eds., Elsevier, Amsterdam, 1982, pp. 27–36.

    Google Scholar 

  15. R.M. German and B.H. Rabin:Powder Metall., 1985, vol. 28, pp. 7–12.

    Article  CAS  Google Scholar 

  16. G.H. Gessinger and H.F. Fischmeister:J. Less-Common Met., 1972, vol. 27, pp. 129–41.

    Article  CAS  Google Scholar 

  17. R.M. German:Sci. Sintering, 1983, vol. 15, pp. 27–42.

    Google Scholar 

  18. G.V. Samsonov and V.I. Yakovlev:Sov. Powder Metall. Met. Ceram., 1967, vol. 6, pp. 548–51.

    Article  Google Scholar 

  19. G.V. Samsonov and V.l. Yakovlev:Sov. Powder Metall. Met. Ceram., 1967, vol. 6, pp. 606–11.

    Article  Google Scholar 

  20. G.V. Samsonov and V.l. Yakovlev:Sov. Powder Metall. Met. Ceram., 1969, vol. 8, pp. 804–08.

    Article  Google Scholar 

  21. G.V. Samsonov and V.l. Yakovlev:Sov. Powder Metall. Met. Ceram., 1970, vol. 9, pp. 30–36.

    Article  Google Scholar 

  22. G.V. Samsonov, I.F. Pryadko, and L.F. Pryadko:A Configurational Model of Matter, Consultants Bureau, New York, NY, 1973.

    Book  Google Scholar 

  23. G.V. Samsonov and V.l. Yakovlev:Sci. Sintering, 1975, vol. 7, pp. 231–40.

    CAS  Google Scholar 

  24. I.H. Moon and J.S. Lee:Powder Metall. Int., 1977, vol. 9, pp. 23–24.

    CAS  Google Scholar 

  25. I.H. Moon and J.S. Lee:Powder Metall., 1979, vol. 22, pp. 5–7.

    Article  CAS  Google Scholar 

  26. J. Whittenauer and T.G. Nieh:Tungsten and Tungsten Alloys, A. Crowson and E.S. Chen, eds., TMS, Warrendale, PA, 1991, pp. 21–26.

    Google Scholar 

  27. J.L. Johnson and R.M. German:Advances in Powder Metallurgy, L.F. Pease and R.J. Sansoucy, eds., MPIF-APMI, Princeton, NJ, 1991, vol. 6, pp. 391–403.

    Google Scholar 

  28. J.J. Burton and E.S. Machlin:Phys. Rev. Lett., 1976, vol. 37, pp. 1433–36.

    Article  CAS  Google Scholar 

  29. J.H. Brophy, H.W. Hayden, and J. Wulff:Powder Metall., W. Leszynski, ed., AIME-MPI, Interscience, New York, NY, 1961, vol. 35, pp. 113–35.

    Google Scholar 

  30. G.H. Gessinger, H.F. Fischmeister, and H.L. Lukas:Acta Metall., 1973, vol. 21, pp. 715–24.

    Article  CAS  Google Scholar 

  31. G.H. Gessinger, H.F. Fischmeister, and H.L. Lukas:Powder Metall., 1973, vol. 16, pp. 119–27.

    Article  CAS  Google Scholar 

  32. W.D. Kingery:J. Appl. Phys., 1959, vol. 30, pp. 301–06.

    Article  CAS  Google Scholar 

  33. I.H. Moon and W.J. Huppmann:Powder Metall. Int., 1974, vol. 6, pp. 190–94.

    CAS  Google Scholar 

  34. J.P. Jones and A.D. Martin:Surf. Sci., 1974, vol. 41, pp. 559–80.

    Article  Google Scholar 

  35. Binary Alloy Phase Diagrams, T.B. Massalski, ed., ASM, Metals Park, OH, 1986.

    Google Scholar 

  36. J.L. Johnson and R.M. German: Pennsylvania State University, University Park, PA, unpublished research, 1992.

  37. V.N. Ermenko, R.V. Minakova, and M.M. Churakov:Sov. Powder Metall. Met. Ceram., 1976, vol. 15, pp. 283–86.

    Google Scholar 

  38. N.C. Kothari:J. Less-Common Met., 1967, vol. 13, pp. 457–68.

    Article  CAS  Google Scholar 

  39. A. Crowson:Modern Developments in Powder Metallurgy, E.N.Aqua and C.I. Whitman, eds., MPIF-APMI, Princeton, NJ, 1985, vol. 15, pp. 507–20.

    Google Scholar 

  40. A. Belhadjhamida and R.M. German:Tungsten and Tungsten Alloys, A. Crowson and E.S. Chen, eds., TMS, Warrendale, PA, 1991, pp. 3–19.

    Google Scholar 

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  1. Pennsylvania State University, 16802-6809, University Park, PA

    J. L. Johnson (Research Assistant) & R. M. German (Brush Chair in Materials)

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  1. J. L. Johnson
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Johnson, J.L., German, R.M. Phase Equilibria Effects on the Enhanced Liquid Phase Sintering of Tungsten-Copper. Metall Trans A 24, 2369–2377 (1993). https://doi.org/10.1007/BF02646516

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