DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES

Gebhardt, E; Kirner, K

Title: DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES (in German)

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Abstract

The diffusion in couples of polycrystalline tungsten and niobium was studied by means of the microhardness method. A number of alloy butions were arc melted, annealed, and hardness checked in order to get a hardness vs. concentration plot from which the hardness values of the diffusion samples could be converted to concentration values. The hardness graph of the completely miscible W-Nb system had a maximum at approximately 40 at.% Nb. The diffusion couples were held at 2100 and 1900 deg C for times up to 500 hours. The diifusion coefficients were calculated according to the Matano method. They proved to depend very much on the concentration and increased from the W side of the system to the Nb side by two orders of magnitude. D = 1.6 x 10/sup -7/ cm/ sup 2//sec for 10 at.% Nb--90 at.% W, D = 1.4 x 10/sup -6/ cm/sup 2//sec for 90 at.% Nb-10 at.% W at 2100 deg C, and D = 5 x 10/sup -9/ cm/sup 2//sec for 10 at.% Nb-90 at.% W, D = 1.16 X 10/sup -7/ cm/sup 2//sec for 90 at.% Nb-10 at.% W at 1900 deg C, respectively. The diffusion coefficient proved to depend strongly on themore »« less

Authors:: Gebhardt, E; Kirner, K

Publication Date:: Thu Aug 01 00:00:00 EDT 1963

Research Org.:: Max-Planck-Institut fur Metallforschung, Stuttgart

OSTI Identifier:: 4630523

NSA Number:: NSA-17-037553

Resource Type:: Journal Article

Journal Name:: Z. Metallk.

Additional Journal Information:: Journal Volume: Vol: 54; Other Information: Orig. Receipt Date: 31-DEC-63

Country of Publication:: Country unknown/Code not available

Language:: German

Subject:: METALS, CERAMICS, AND OTHER MATERIALS; ACTIVATION ENERGY; ANNEALING; CRYSTALS; DIFFUSION; ELECTRIC ARCS; HARDNESS; HIGH TEMPERATURE; MELTING; NIOBIUM ALLOYS; NUMERICALS; PHASE DIAGRAMS; SAMPLING; THERMODYNAMICS; TUNGSTEN ALLOYS

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                    Gebhardt, E, and Kirner, K. DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES.  Country unknown/Code not available: N. p., 1963. 
        Web.

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                    Gebhardt, E, & Kirner, K. DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES.  Country unknown/Code not available.

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                    Gebhardt, E, and Kirner, K. 1963.  
        "DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES".  Country unknown/Code not available.

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@article{osti_4630523,

  title        = {DIFFUSION INVESTIGATION IN THE TUNGSTEN-NIOBIUM SYSTEM ON POLYCRYSTALLINE, SINGLE-CRYSTAL, AND SPRAYED COUPLES. I. POLYCRYSTALLINE COUPLES},

  author       = {Gebhardt, E and Kirner, K},

  abstractNote = {The diffusion in couples of polycrystalline tungsten and niobium was studied by means of the microhardness method. A number of alloy butions were arc melted, annealed, and hardness checked in order to get a hardness vs. concentration plot from which the hardness values of the diffusion samples could be converted to concentration values. The hardness graph of the completely miscible W-Nb system had a maximum at approximately 40 at.% Nb. The diffusion couples were held at 2100 and 1900 deg C for times up to 500 hours. The diifusion coefficients were calculated according to the Matano method. They proved to depend very much on the concentration and increased from the W side of the system to the Nb side by two orders of magnitude. D = 1.6 x 10/sup -7/ cm/ sup 2//sec for 10 at.% Nb--90 at.% W, D = 1.4 x 10/sup -6/ cm/sup 2//sec for 90 at.% Nb-10 at.% W at 2100 deg C, and D = 5 x 10/sup -9/ cm/sup 2//sec for 10 at.% Nb-90 at.% W, D = 1.16 X 10/sup -7/ cm/sup 2//sec for 90 at.% Nb-10 at.% W at 1900 deg C, respectively. The diffusion coefficient proved to depend strongly on the temperature. From a (log D-1/T) plot the activation energy was calculated. The values were high, compared with the values from other diffusion studies. (auth)},

  doi          = {},

  url          = {https://www.osti.gov/biblio/4630523},
  journal      = {Z. Metallk.},
number       = ,

  volume       = Vol: 54,

  place        = {Country unknown/Code not available},

  year         = {Thu Aug 01 00:00:00 EDT 1963},

  month        = {Thu Aug 01 00:00:00 EDT 1963}

}

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