Advertisement

Metals and Materials International

, Volume 25, Issue 6, pp 1428–1435 | Cite as

Thermal Decomposition of Massive Phase to Fine Lamellar α/β in Ti–6Al–4V Additively Manufactured Alloy by Directed Energy Deposition

  • Ghozali Suprobo
  • Abdul Azis Ammar
  • Nokeun ParkEmail author
  • Eung Ryul BaekEmail author
  • Sungwook Kim
Article

Abstract

The occurrence of a massive phase (αm) transformation and a thermal decomposition of an αm to fine lamellar α/β with an α lamellar width of approximately 1 µm have been identified in additively manufactured Ti–6Al–4V alloy by directed energy deposition. The β to αm phase transformation during additive manufacturing generated a high dislocation density, which was calculated by the kernel average misorientation. This caused a significant change in the Gibbs free energy of α, resulting in the nucleation of the β phase becoming preferable in the area with high dislocation density at temperature below the β-transus temperature. Subsequent annealing at 850 °C altered the massive morphology to lamellar due to the formation of a β phase between α lamellar boundaries.

Graphical Abstract

Keywords

Massive phase transformation Titanium alloys Dislocation Misorientation Phase stability Additive manufacturing 

Notes

Acknowledgements

This work was supported by the Korea Evaluation Institute of Industrial Technology (KEIT) Granted financial resource from Ministry of Trade, Industry, and Energy, Republic of Korea (No. 10062485) and IONS Co. Ltd.

References

  1. 1.
    T. Kumagai, E. Abe, M. Takeyama, M. Nakamura, Microstructural evolution of massively transformed γ-tial during isothermal aging. Scr. Mater. 36, 523–529 (1997).  https://doi.org/10.1016/S1359-6462(96)00416-2 CrossRefGoogle Scholar
  2. 2.
    P. Wang, V.K. Vasudevan, Composition dependence of the massive transformation from α to γ in quenched TiAl alloys. Scr. Metall. Mater. 27, 89–94 (1992).  https://doi.org/10.1016/0956-716X(92)90325-9 CrossRefGoogle Scholar
  3. 3.
    S.L. Lu, M. Qian, H.P. Tang, M. Yan, J. Wang, D.H. StJohn, Massive transformation in Ti–6Al–4V additively manufactured by selective electron beam melting. Acta Mater. 104, 303–311 (2016).  https://doi.org/10.1016/j.actamat.2015.11.011 CrossRefGoogle Scholar
  4. 4.
    A. Denquin, S. Naka, Phase transformation mechanisms two-phase discontinuous coarsening and massive-type transformation. Acta Mater. 44, 353–365 (1996).  https://doi.org/10.1016/1359-6454(95)00168-6 CrossRefGoogle Scholar
  5. 5.
    Z. Liu, S.L. Lu, H.P. Tang, M. Qian, L. Zhan, Characterization and decompositional crystallography of the massive phase grains in an additively-manufactured Ti–6Al–4V alloy. Mater. Charact. 127, 146–152 (2017).  https://doi.org/10.1016/j.matchar.2017.01.012 CrossRefGoogle Scholar
  6. 6.
    T. Ahmed, H.J. Rack, Phase transformations during cooling in α + β titanium alloys. Mater. Sci. Eng. A 243, 206–211 (1998).  https://doi.org/10.1016/S0921-5093(97)00802-2 CrossRefGoogle Scholar
  7. 7.
    M. Plichta, J. Williams, H. Aaronson, On the existence of the β → αm transformation in the alloy systems Ti–Ag, Ti–Au, and Ti–Si. Metall. Trans. A 8, 1885–1892 (1977).  https://doi.org/10.1007/BF02646561 CrossRefGoogle Scholar
  8. 8.
    R.W. Cahn, P. Haasen, Physical Metallurgy, 4th edn. (North Holland, Amsterdam, 1996)Google Scholar
  9. 9.
    C. Körner, F. Group, C. Körner, Additive manufacturing of metallic components by selective electron beam melting—a review. Int. Mater. Rev. 61, 361–377 (2016).  https://doi.org/10.1080/09506608.2016.1176289 CrossRefGoogle Scholar
  10. 10.
    S. Wolff, T. Lee, E. Faierson, K. Ehmann, J. Cao, Anisotropic properties of directed energy deposition (DED)-processed Ti–6Al–4V. J. Manuf. Process. 24, 397–405 (2016).  https://doi.org/10.1016/j.jmapro.2016.06.020 CrossRefGoogle Scholar
  11. 11.
    A. Saboori, D. Gallo, S. Biamino, P. Fino, M. Lombardi, An overview of additive manufacturing of titanium components by directed energy deposition: microstructure and mechanical properties. Appl. Sci. 7, 883 (2017).  https://doi.org/10.3390/app7090883 CrossRefGoogle Scholar
  12. 12.
    D. Kotoban, A. Nazarov, I. Shishkovsky, Comparative study of selective laser melting and direct laser metal deposition of Ni 3 Al intermetallic alloy. Procedia IUTAM 23, 138–146 (2017).  https://doi.org/10.1016/j.piutam.2017.06.014 CrossRefGoogle Scholar
  13. 13.
    B.D. La Batut, O. Fergani, V. Brotan, M. Bambach, Analytical and numerical temperature prediction in direct metal deposition of Ti6Al4V. J. Manuf. Mater. Process. 1, 1–14 (2017).  https://doi.org/10.3390/jmmp1010003 CrossRefGoogle Scholar
  14. 14.
    S.S. Al-Bermani, M.L. Blackmore, W. Zhang, I. Todd, The origin of microstructural diversity, texture, and mechanical properties in electron beam melted Ti–6Al–4V. Metall. Mater. Trans. A 41, 3422–3434 (2010).  https://doi.org/10.1007/s11661-010-0397-x CrossRefGoogle Scholar
  15. 15.
    S. Price, B. Cheng, J. Lydon, K. Cooper, K. Chou, On process temperature in powder-bed electron beam additive manufacturing: process parameter effects. J. Manuf. Sci. Eng. 136, 061019 (2014).  https://doi.org/10.1115/1.4028485 CrossRefGoogle Scholar
  16. 16.
    T.H. Lee, M. Kang, J.H. Oh, D.H. Kam, Manufacturing, parametric study of STS 316L deposition with arc and wire additive manufacturing. J. Weld. Join. 36, 23–30 (2018)CrossRefGoogle Scholar
  17. 17.
    G. Lu, Influence of processing on microstructure and mechanical properties of (α + β) titanium alloys. Mater. Sci. Eng. A 243, 32–45 (1998).  https://doi.org/10.1016/S0921-5093(97)00778-8 CrossRefGoogle Scholar
  18. 18.
    O.M. Ivasishin, D.G. Savvakin, The impact of diffusion on synthesis of high-strength titanium alloys from elemental powder blends. Key Eng. Mater. 436, 113–121 (2010).  https://doi.org/10.4028/www.scientific.net/KEM.436.113 CrossRefGoogle Scholar
  19. 19.
    M.J. Donachie, Jr., Titanium: A Technical Guide, 2nd ed. (ASM Int., Ohio, 2000)Google Scholar
  20. 20.
    I. Katzarov, S. Malinov, W. Sha, Finite element modeling of the morphology of β to α phase transformation in Ti-6Al-4V alloy. Metall. Mater. Trans. A 33, 1027–1040 (2002).  https://doi.org/10.1007/s11661-002-0204-4 CrossRefGoogle Scholar
  21. 21.
    C. Moussa, M. Bernacki, R. Besnard, N. Bozzolo, About quantitative EBSD analysis of deformation and recovery substructures in pure Tantalum. IOP Conf. Ser. Mater. Sci. Eng. 89, 012038 (2015).  https://doi.org/10.1088/1757-899X/89/1/012038 CrossRefGoogle Scholar
  22. 22.
    L.P. Kubin, A. Mortensen, Geometrically necessary dislocations and strain-gradient plasticity: a few critical issues. Scr. Mater. 48, 119–125 (2003).  https://doi.org/10.1016/S1359-6462(02)00335-4 CrossRefGoogle Scholar
  23. 23.
    H. Wu, J. Jiang, H. Liu, J. Sun, Y. Gu, R. Tang, X. Zhao, A. Ma, Fabrication of an ultra-fine grained pure titanium with high strength and good ductility via ECAP plus cold rolling. Metals 7, 563 (2017).  https://doi.org/10.3390/met7120563 CrossRefGoogle Scholar
  24. 24.
    S. Brinckmann, T. Siegmund, Y. Huang, A dislocation density based strain gradient model. Int. J. Plast 22, 1784–1797 (2006).  https://doi.org/10.1016/j.ijplas.2006.01.005 CrossRefGoogle Scholar
  25. 25.
    T. Kunieda, M. Nakai, Y. Murata, T. Koyama, M. Morinaga, Estimation of the system free energy of martensite phase in an Fe–Cr–C ternary alloy. ISIJ Int. 45, 1909–1914 (2005).  https://doi.org/10.2355/isijinternational.45.1909 CrossRefGoogle Scholar
  26. 26.
    J.D. Beal, R. Boyer, D. Sanders, T.B. Company, forming of titanium and titanium alloys, in: ASM Handbook 14B, Metalworking: Sheet Forming, ed. S.L. Semiatin (ASM Int., Russell Township, 2006), pp. 656–669Google Scholar
  27. 27.
    G.E. Dieter, D. Bacon, Mechanical Metallurgy: SI Metric Edition (McGraw-Hill Book Company, London, 1988)Google Scholar
  28. 28.
    K. Mutombo, C. Siyasiya, W.E. Stumpf, Dynamic globularization of α-phase in Ti6Al4V alloy during hot compression. Mater. Sci. Forum 783–786, 584–590 (2014).  https://doi.org/10.4028/www.scientific.net/MSF.783-786.584 CrossRefGoogle Scholar
  29. 29.
    G.R. Love, Dislocation pipe diffusion. Acta Metall. 12, 731–737 (1964).  https://doi.org/10.1016/0001-6160(64)90220-2 CrossRefGoogle Scholar
  30. 30.
    H.D. Brody, S.A. David, Application of Solidification Theory to Titanium Alloys, in The Science Technology and Application of Titanium, ed. by R.I. Jaffe, N.E. Promisel (Pergamon, Oxford, 1970), pp. 21–34CrossRefGoogle Scholar
  31. 31.
    R. Boyer, G. Welsch, E.W. Collings, ASM Materials Properties Handbook: Titanium Alloys (ASM Int., Russell Township, 1994)Google Scholar
  32. 32.
    G. Lütjering, J.C. Williams, Titanium (Springer, Berlin, 2003)CrossRefGoogle Scholar
  33. 33.
    G.Q. Wu, C.L. Shi, W. Sha, A.X. Sha, H.R. Jiang, Effect of microstructure on the fatigue properties of Ti–6Al–4V titanium alloys. Mater. Des. 46, 668–674 (2013).  https://doi.org/10.1016/j.matdes.2012.10.059 CrossRefGoogle Scholar
  34. 34.
    R.K. Nalla, B.L. Boyce, J.P. Campbell, J.O. Peters, R.O. Ritchie, Influence of microstructure on high-cycle fatigue of Ti–6Al–4V: bimodal vs. lamellar structures. Metall. Mater. Trans. A 33, 899–918 (2002).  https://doi.org/10.1007/s11661-002-0160-z CrossRefGoogle Scholar

Copyright information

© The Korean Institute of Metals and Materials 2019

Authors and Affiliations

  1. 1.School of Materials Science and EngineeringYeungnam UniversityGyeongsanRepublic of Korea
  2. 2.Industrial Materials Research GroupResearch Institute of Industrial Science and TechnologyPohangRepublic of Korea
  3. 3.Institute of Materials TechnologyYeungnam UniversityGyeongsan-siSouth Korea

Personalised recommendations