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Microstructural evolution in laser-deposited multilayer Ti-6Al-4V builds: Part II. Thermal modeling

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Abstract

The thermal history developed in laser metal deposition (LMD) processes has been shown to be quite complex and results in the evolution of an equally complex microstructure. A companion article (Part I. Microstructural Characterization) discussed the LMD of Ti-6Al-4V, where the resultant microstructure consists of a periodic, scale-graded layer of basketweave Widmanstätten alpha and a banding that consists of colony Widmanstätten alpha. In order to understand the microstructural evolution in Ti-6Al-4V, a numerical thermal model based on the implicit finite-difference technique was developed to model LMD processes. The effect of different laser-scan velocities on the characteristics of the thermal history was investigated using an eight-layer single-line build. As the laser-scan speed decreases and the position within a layer increases, the peak temperature increases. The heating rate and the peak thermal gradient within a deposited layer were shown to follow the same trend as the peak temperature after two layers were deposited on top of the substrate. In general, the laser-scan speed or z-position within a layer did not have a significant effect on the cooling rate. The cooling rate in a newly deposited layer decreases as the number of layer additions increases. Given the predicted temperature vs time profile from the thermal model, the evolution of phase transformations occurring in the deposit is mapped as each layer is deposited. As a result of the thermal cycling imposed by the periodic deposition of material, a characteristic layer, consisting of two regions heated above and below the beta transus, forms in layer n due to the deposition of layer n+1.

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References

  1. S.M. Kelly and S.L. Kampe: Metall. Mater. Trans. A, 2004, vol. 35A, pp. 1861–67.

    CAS  Google Scholar 

  2. M.L. Griffith, M.T. Ensz, J.D. Puskar, C.V. Robino, J.A. Brooks, J.A. Philliber, J.E. Smugeresky, and W.H. Hofmeister: in Solid Freeform and Additive Fabrication—2000, S.C. Danforth, D. Dimos, and F.B. Prinz, eds., Materials Research Society, Warrendale, PA, 2000, vol. 625, pp. 9–20.

    Google Scholar 

  3. M.L. Griffith, E. Schlienger, L.D. Harwell, M.S. Oliver, M.D. Baldwin, M.T. Ensz, M. Essien, J. Brooks, C.V. Robino, J.E. Smugeresky, W.H. Hofmeister, M.J. Wert, and D.V. Nelson: Mater. Design, 1999, vol. 20, pp. 107–13.

    Article  Google Scholar 

  4. L. Costa, T. Reti, A.M. Deus, and R. Vilar: Proc. 2002 Int. Conf. on Metal Powder Deposition for Rapid Manufacturing, D.M. Keicher, J.W. Sears, and J.E. Smugeresky, eds., Metal Powder Industries Federation, Princeton, NJ, 2002, pp. 172–79.

    Google Scholar 

  5. W.H. Hofmeister, M.L. Griffith, M.T. Ensz, and J.E. Smugeresky: JOM, 2001, vol. 53 (9), pp. 30–34.

    CAS  Google Scholar 

  6. W.H. Hofmeister, M.J. Wert, J.E. Smugeresky, J.A. Philliber, M.L. Griffith, and M.T. Ensz: JOM, 1999, vol. 51 (7) (http://www.tms.org/pubs/journals/JOM/9907/Hofmeister/Hofmeister-9907.html).

  7. A. Vasinota, J. Beuth, and M.L. Griffith: in Solid Freeform Fabrication Proc., D. Bourell, J. Beaman, R. Crawford, H. Marcus, and J. Barlow, eds., University of Texas, Austin, TX, 1999, pp. 383–91.

    Google Scholar 

  8. P.A. Kobryn and S.L. Semiatin: in Solid Freeform Fabrication Proc., D. Bourell, J. Beaman, R. Crawford, H. Marcus, and J. Barlow, eds., University of Texas, Austin, TX, 2000, pp. 58–65.

    Google Scholar 

  9. P.A. Kobryn and S.L. Semiatin: JOM, 2001, vol. 53 (9), pp. 40–42.

    CAS  Google Scholar 

  10. M.N. Özisik: Finite Difference Methods in Heat Transfer, CRC, Ann Arbor, MI, 1997.

    Google Scholar 

  11. S. Wolfram: Mathematica, 1998–2002.

  12. S.M. Kelly: Master’s Thesis, Virginia Tech, Blacksburg, VA (http://scholar.lib.vt.edu/theses/available/etd-05222002-223436/), 2002.

    Google Scholar 

  13. K.C. Mills: Recommended Values of Thermophysical Properties for Selected Commercial Alloys, Woodhead, Cambridge, United Kingdom, 2002.

    Google Scholar 

  14. F.G. Arcella and F.H. Froes: JOM, 2000, vol. 52 (5), pp. 28–30.

    CAS  Google Scholar 

  15. T.J. Wieting and J.T. Schriempf: J. Appl. Phys., 1976, vol. 47, pp. 4009–11.

    Article  CAS  Google Scholar 

  16. C. Hu and T.N. Baker: J. Mater. Processing Technol., 1999, vol. 94, pp. 116–22.

    Article  Google Scholar 

  17. V.M. Majdic and G. Ziegler: Z. Metallk., 1973, vol. 64, pp. 751–58.

    CAS  Google Scholar 

  18. T. Ahmed and H.J. Rack: Mater. Sci. Eng. A, 1998, vol. 243, pp. 206–11.

    Article  Google Scholar 

  19. T. DebRoy and S.A. David: Rev. Modern Phys., 1995, vol. 67, pp. 85–112.

    Article  CAS  Google Scholar 

  20. K. Mundra, T. DebRoy, S.S. Babu, and S.A. David: Welding J., 1997, vol. 76, pp. 163s-171s.

    Google Scholar 

  21. B.A.B. Anderrson: J. Eng. Mater. Technol., 1978, vol. 100, pp. 356–62.

    Google Scholar 

  22. J. Goldak, A. Chakravarti, and M. Bibby: Metall. Trans. B, 1984, vol. 15B, pp. 299–305.

    Google Scholar 

  23. I. Katzarov, S. Malinov, and W. Sha: Metall. Mater. Trans. A, 2002, vol. 33A, pp. 1027–40.

    Article  CAS  Google Scholar 

  24. F.J. Gil, J.M. Manero, and J.A. Planell: in Titanium ’95: Proc. 8th World Conf. on Titanium. H.M. Flower, ed., IOM, London, 1996, vol. 3, pp. 2454–61.

    Google Scholar 

  25. F.X. Gil Mur, D. Rodriguez, and J.A. Planell: J. Alloys Compounds, 1996, vol. 234, pp. 287–89.

    Article  CAS  Google Scholar 

  26. J.C. Chesnutt, C.G. Rhodes, and J.C. Williams: in Titanium and Titanium Alloys, M.J. Donachie, ed., ASM, Materials Park, OH, 1982, pp. 100–39.

    Google Scholar 

  27. O.M. Ivasishin: Proc. 6th World Conf. on Titanium, G. Beranger, ed., Les Editions de Physique, Les Ulis Cedex, France, 1989, pp. 1535–39.

    Google Scholar 

  28. G. Lütjering, J. Albrecht, and O.M. Ivasishin: in Microstructure/Property Relationships of Titanium Alloys, J.A. Hall, ed., TMS, Warrendale, PA, 1994, pp. 65–75.

    Google Scholar 

  29. O.M. Ivasishin and G. Lütjering: Mater. Sci. Eng. A, 1993, vol. 168, pp. 23–28.

    Article  Google Scholar 

  30. W. Szkliniarz and G. Smolka: J. Mater. Processing Technol., 1995, vol. 53, pp. 413–22.

    Article  Google Scholar 

  31. P.S. Goodwin, C. Mitchell, J. Liang, J. Mei, and X. Wu: Proc. 2002 Int. Conf. on Metal Powder Deposition for Rapid Manufacturing, D.M. Keicher, J.W. Sears, and J.E. Smugeresky, eds., Metal Powder Industries Federation, Princeton, NJ, 2002, pp. 87–95.

    Google Scholar 

  32. P.A. Kobryn, E.H. Moore, and S.L. Semiatin: Scripta Mater., 2000, vol. 43, pp. 299–305.

    Article  CAS  Google Scholar 

  33. S.M. Kelly: Oak Ridge National Laboratory, Oak Ridge, TN, unpublished research, 2004.

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Authors and Affiliations

  1. the Materials Science and Engineering Department, Virginia Tech, 24061-0237, Blacksburg, VA

    S. M. Kelly (Graduate Research Assistant) & S. L. Kampe (Associate Professor)

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  1. S. M. Kelly
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  2. S. L. Kampe
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Kelly, S.M., Kampe, S.L. Microstructural evolution in laser-deposited multilayer Ti-6Al-4V builds: Part II. Thermal modeling. Metall Mater Trans A 35, 1869–1879 (2004). https://doi.org/10.1007/s11661-004-0095-7

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  • DOI: https://doi.org/10.1007/s11661-004-0095-7

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