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Electron-Beam Atomic Spectroscopy for In Situ Measurements of Melt Composition for Refractory Metals: Analysis of Fundamental Physics and Plasma Models

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Abstract

Electron-beam (EB) melting is used for the processing of refractory metals, such as Ta, Nb, Mo, and W. These metals have high value and are critical to many industries, including the semiconductor, aerospace, and nuclear industries. EB melting can also purify secondary feedstock, enabling the recovery and recycling of these materials. Currently, there is no method for measuring melt composition in situ during EB melting. Optical emission spectroscopy of the plasma generated by EB impact with vapor above the melt, a technique here termed electron-beam atomic spectroscopy, can be used to measure melt composition in situ, allowing for analysis of melt dynamics, facilitating improvement of EB melting processes and aiding recycling and recovery of these critical and high-value metals. This paper reviews the physics of the plasma generation by EB impact by characterizing the densities and energies of electrons, ions, and neutrals, and describing the interactions between them. Then several plasma models are introduced and their suitability to this application analyzed. Lastly, a potential method for calibration-free composition measurement is described and the challenges for implementation addressed.

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Abbreviations

ε :

Energy of a particle (electron, ion, neutral), eV

k :

Boltzmann’s constant

T e :

Electron temperature, eV

T b :

Bulk electron temperature, eV

T hot :

Hot electron group temperature, eV

T x :

Electron temperature for x-form EEDF, eV

C :

Non-dimensional constant

φ :

Photon flux on a detector, photons/second

σ :

Cross section, cm2

n 0 :

Neutral atom density, cm−3

n e :

Electron density, cm−3

Γ(x):

Gamma function of x

A ij :

Einstein coefficient for transition between state i and j, s−1

f(x):

Electron energy distribution function

f M(x):

Maxwellian electron energy distribution function

α :

Ionized fraction of vapor particles

α EB :

Ionized fraction due to EB impact

α SE :

Ionized fraction due to secondary electron (SE) impact

l EB :

Length of EB interaction with vapor, cm

l SE :

Length of SE interaction with vapor, cm

I EB :

EB current

I SE :

SE current

v a :

Neutral vapor atomic velocity

A EB :

Cross-sectional area of EB impact with vapor

P :

Vapor density, cm−3

m e :

Electron mass

References

  1. American Chemical Society: “Endangered Elements.” http://www.acs.org/content/acs/en/greenchemistry/research-innovation/research-topics/endangered-elements.html. Accessed Sept 2014.

  2. A.A. Ahern: “The 2011 U.S. Endangered Elements List,” American Elements.http://www.americanelements.com/2011Endangered_Elements_List.html. Accessed Sept 2014.

  3. A.A. Ahern: “2nd Annual U.S. Endangered Elements List,” American Elements. http://www.americanelements.com/2012Endangered_Elements_List.html. Accessed Sept 2014.

  4. M. Pitts: “Endangered Elements Periodic Table,” Chemistry Innovation Knowledge Transfer Network. https://connect.innovateuk.org/web/sustainability-theme1/article-view/-/blogs/endangered-elements-periodic-table?p_p_auth=R7kxL8FV. Accessed Sept 2014.

  5. T. Graedel, J. Allwood, J.P. Birat, B.K. Reck, S.F. Sibley, G. Sonnemann, M. Buchert, C. Hageluken: “Recycling Rates of Metals—A Status Report, A Report of the Working Group on the Global Metal Flows to the International Resource Panel,” United Nations Environment Programme, 2011.

  6. A. Majumder, G.K. Sahu, K.B. Thakur, and V.K. Mago: J. Phys. D: Appl. Phys., 2010, vol. 43 (7), pp. 075204.

    Article  Google Scholar 

  7. B. Dikshit, G.R. Zende, M.S. Bhatia, and B. Suri: IEEE Trans. Plasma Sci., 2009, vol. 27 (7), pp. 1196-202.

    Article  Google Scholar 

  8. D. Levko, Y.E. Krasik, W. An, and G. Mueller: J. Appl. Phys., 2013, vol. 113 (12), pp. 123302.

    Article  Google Scholar 

  9. E. Besuelle and J. Nicolai: J. Appl. Phys., 1998, vol. 84 (8), pp. 4114-21.

    Article  Google Scholar 

  10. R. Nishio, K. Tuchida, M. Tooma, and K. Suzuki: J. Appl. Phys., 1992, vol. 72 (10), pp. 4548-55.

    Article  Google Scholar 

  11. R. Nishio and K. Suzuki: J. Nucl. Sci. Technol., 1994, vol. 31 (6), pp. 572-81.

    Article  Google Scholar 

  12. W. An, Y.E. Krasik, R. Fetzer, B. Bazylev, G. Mueller, A. Weisenburger, and V. Bernshtam: J. Appl. Phys., 2011, vol. 110(9), p. 093304.

    Article  Google Scholar 

  13. V. Kumar, T. Barnwal, J. Mukherjee, and L. Gantayet: J. Phys.: Conf. Ser., 2010, vol. 208(1), p. 012133.

    Google Scholar 

  14. J. Goldstein, D. Newbury, D. Joy, C. Lyman, P. Echlin, E. Lifshin, L. Sawyer, and J. Michael: Electron Microscopy and X-Ray Microanalysis, Springer Science, New York, NY, 2003, pp. 75-88.

    Book  Google Scholar 

  15. M. Hakala, C. Corbel, and R.M. Nieminem: J. Phys. D: Appl. Phys., 2005, vol. 38 (5), pp. 711-21.

    Article  Google Scholar 

  16. E. Reinhold and J. Faber: Surf. Coat. Technol., 2011, vol. 206 (7), pp. 1653-59.

    Article  Google Scholar 

  17. H. Sugai, I. Ghanashev, M. Hosokawa, K. Mizuno, K. Nakamura, H. Toyoda, K. Yamauchi: Plasma Sources Sci. Technol., 2001, vol. 10 (2), pp. 378-85.

    Article  Google Scholar 

  18. A Grill: Cold Plasma Materials Fabrication: From Fundamentals to Applications, Wiley, New York, NY, 1994.

  19. Kent Lab: “Vapor Pressure”, NYU Physics. http://www.physics.nyu.edu/kentlab/How_to/ChemicalInfo/VaporPressure/morepressure.pdf. Accessed May 2014.

  20. T. Asano, N. Uetake, and K. Suzuki: J. Nucl. Sci. Technol., 1992, vol. 29 (12), pp. 1194-200.

    Article  Google Scholar 

  21. Y.-K. Kim: Phys. Rev. A., 2001, vol. 64 (3), p. 032713.

    Article  Google Scholar 

  22. P. Bartlett and A. Stelbovics: At. Data Nucl. Data Tables, 2004, vol. 86, pp. 235-365.

    Article  Google Scholar 

  23. K. Bartschat, A. Dasgupta, and J. Giuliani: J. Phys. B: At. Mol. Opt. Phys., 2002, vol. 35, pp. 2899-909.

    Article  Google Scholar 

  24. H. Chung, R. Lee, M. Chen, and Y. Ralchenko: “The How To For FLYCHK @ NIST”, National Institute of Standards and Technology, Gaithersburg, MD, 2008.

    Google Scholar 

  25. V. Engelko and G. Mueller: J. Appl. Phys., 2005, vol. 98 (1), pp. 013303.

    Article  Google Scholar 

  26. I. Krinberg and G. Mladenov: Vacuum, 2005, vol. 77 (4), pp. 407-411.

    Article  Google Scholar 

  27. A. Majumder, B. Dikshit, M. Bhatia, and V. Mago: Rev. Sci. Instrum., 2008, vol. 79 (9), pp. 093305.

    Article  Google Scholar 

  28. M. Guerra, F. Parente, P. Indelicato, and J. Santos: Int. J. Mass. Spectrom., 2012, vol. 313, pp. 1-7.

    Article  Google Scholar 

  29. A. Ciucci, M. Corsi, V. Pallaeschi, S. Rastelli, A. Salvetti, E. Tognoni: Appl. Spectrosc., 1999, vol. 53 (8), pp. 960-64.

    Article  Google Scholar 

  30. T. Fujimoto and R.W.P McWhirter: Phys. Rev. A, 1990, vol. 42 (11), pp. 6588-601.

    Article  Google Scholar 

  31. X.-M. Zhu and Y.-K. Pu: J. Phys. D: Appl. Phys., 2010, vol. 43, pp. 015204.

    Article  Google Scholar 

  32. D. Mihailova, J. van Dijk, M. Grozeva, G. Degrez, J.J.A.M. van der Mullen: J. Phys. D: Appl. Phys., 2011, vol. 44, pp. 194001.

    Article  Google Scholar 

  33. G. Petrov, D. Boris, Tz. Petrova, E. Lock, R. Fernsler, S. Walton: Plasma Sourc. Sci. Technol., 2013, vol. 22, pp. 065005.

    Article  Google Scholar 

  34. J.B. Boffard, C.C. Lin, and C.A. DeJoseph Jr: J. Phys. D: Appl. Phys., 2004, vol. 37, pp. R143-R161.

    Article  Google Scholar 

  35. R.C. Hilborn: “Einstein Coefficients, cross sections, f values, dipole moments, and all that,” Department of Physics, Amherst College, Amherst, MA. http://www.doylegroup.harvard.edu/wiki/images/f/f4/Hilborn.pdf. Accessed May 2014.

  36. National Institute of Standards and Technology: “NIST Atomic Spectra Database Lines Form”, Gaithersburg, MD. http://physics.nist.gov/PhysRefData/ASD/lines_form.html. Accessed May 2014.

  37. P. Smith, C. Heise, J. Esmond, and R. Kurucz: “Atomic spectra line database from CD-ROM 23 of R.L. Kurucz”, Harvard, Cambridge, MA. http://www.cfa.harvard.edu/amp/ampdata/kurucz23/sekur.html. Accessed May 2014.

  38. J.B. Boffard, C.C. Lin, C. Culver, S. Wang, A. Wendt, S. Radovanov, and H. Persing: J. Vac. Sci. Technol., 2014, vol. 32 (2), pp. 021304.

    Article  Google Scholar 

  39. J.B. Boffard, R.O. Jung, C.C. Lin, L. Aneskavich, and A. Wendt: J. Phys. D: Appl. Phys., 2012, vol. 45 (4), pp. 045201.

    Article  Google Scholar 

  40. G.P. Wells: “Electron beam exciter for optical emission spectroscopy and optical excitation cross section analysis in processing systems,” University of Texas at Dallas, Dallas, TX. http://pqdtopen.proquest.com/pqdtopen/doc/1038943211.html?FMT=ABS, 2011. Accessed June 2014.

  41. J.B. Boffard, R.O. Jung, C.C. Lin, L. Aneskavich, A. Wendt: Plasma Sourc Sci. Technol., 2011, vol. 20 (5), pp. 55006.

    Article  Google Scholar 

  42. J. Rudolph and V. Helbig: J. Phys. B: At. Mol. Phys., 1982, vol. 15 (17), pp. L599.

    Article  Google Scholar 

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Acknowledgements

We would like to take this opportunity to thank NSF for the support of the I/UCRC at WPI on Resource Recovery and Recycling. The collaboration with ERCo (R. De Saro) and H.C. Starck (M. Abouaf, P. Aimone, R. Dorvel) is greatly appreciated for providing us their expertise and facilities.

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Authors and Affiliations

  1. Worcester Polytechnic Institute, Worcester, MA, USA

    Paul Joseph Gasper (M.S. Graduate) & Diran Apelian (Director of Metals Processing Institute)

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  1. Paul Joseph Gasper
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Correspondence to Diran Apelian.

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Manuscript submitted October 2, 2014.

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Gasper, P.J., Apelian, D. Electron-Beam Atomic Spectroscopy for In Situ Measurements of Melt Composition for Refractory Metals: Analysis of Fundamental Physics and Plasma Models. Metall Mater Trans B 46, 719–732 (2015). https://doi.org/10.1007/s11663-014-0229-2

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