Microstructure evolution of Inconel 738 fabricated by pulsed laser powder bed fusion

Abstract

High-density crack-free Inconel 738 samples were manufactured into both thin-walled and bulk samples using pulsed laser powder bed fusion (P-LPBF). As-built thin-walled samples presented a dendritic microstructure with primary dendrite arm spacing (PDAS) of 1.02 ± 0.21 µm. This PDAS was consistent along the length of the as-built wall, which led to a homogeneously distributed hardness across the deposit. Energy dispersive spectroscopy (EDS) maps showed near-equilibrium elemental segregation due to limited solute trapping occurring during rapid solidification. In the bulk of the as-built samples, a PDAS of 0.69 ± 0.06 µm was obtained. The smaller dendrite arm spacing which developed in the bulk was a result of the higher cooling rates obtained in this volume of sample. The EDS maps of the bulk samples presented comparative elemental constituents of the different phases as seen in the thin-walled sample. The Electron Backscattered Diffraction (EBSD) map of the bulk sample presented columnar grains with strong texture along the (100) crystallographic orientation planes. After annealing and aging treatment, cuboidal primary γʹ precipitates and secondary γʹ precipitates were observed. No strain–age cracks were found after the heat treatment. The EBSD map displayed comparative results to the as-built condition; with columnar grains with preferred orientation towards (100) planes.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

References

  1. 1.

    Trosch T, Strößner J, Völkl R, Glatzel U (2016) Microstructure and mechanical properties of selective laser melted Inconel 718 compared to forging and casting. Mater Lett 164:428–431. https://doi.org/10.1016/j.matlet.2015.10.136

    Article  Google Scholar 

  2. 2.

    Gao W, Zhang Y, Ramanujan D, Ramani K, Chen Y, Williams CB, Wang CCL, Shin YC, Zhang S, Zavattieri PD (2015) The status, challenges, and future of additive manufacturing in engineering. Comput Aided Des 69:65–89. https://doi.org/10.1016/j.cad.2015.04.001

    Article  Google Scholar 

  3. 3.

    Lippold JC, Kiser SD, DuPont JN (2011) Welding metallurgy and weldability of nickel-base alloys. Wiley, New York

    Google Scholar 

  4. 4.

    Balikci E, Raman A, Mirshams R (2000) Tensile strengthening in the nickel-base superalloy IN738LC. J Mater Eng Perform 9(3):324–329

    Article  Google Scholar 

  5. 5.

    Hays C (2008) Size and shape effects for gamma prime in alloy 738. J Mater Eng Perform 17(2):254–259. https://doi.org/10.1007/s11665-007-9135-y

    Article  Google Scholar 

  6. 6.

    Ojo OA, Chaturvedi MC (2005) On the role of liquated γ′ precipitates in weld heat affected zone microfissuring of a nickel-based superalloy. Mater Sci Eng A 403(1):77–86. https://doi.org/10.1016/j.msea.2005.04.034

    Article  Google Scholar 

  7. 7.

    Ojo O, Richards N, Chaturvedi M (2004) On incipient melting during high temperature heat treatment of cast Inconel 738 superalloy. J Mater Sci 39(24):7401–7404

    Article  Google Scholar 

  8. 8.

    Ojo O, Richards N, Chaturvedi M (2006) Study of the fusion zone and heat-affected zone microstructures in tungsten inert gas-welded INCONEL 738LC superalloy. Metall Mater Trans A 37(2):421–433

    Article  Google Scholar 

  9. 9.

    Ojo OA, Chaturvedi MC (2007) Liquation microfissuring in the weld heat-affected zone of an overaged precipitation-hardened nickel-base superalloy. Metall Mater Trans A 38(2):356–369. https://doi.org/10.1007/s11661-006-9025-1

    Article  Google Scholar 

  10. 10.

    Ojo OA, Richards NL, Chaturvedi MC (2004) Liquid film migration of constitutionally liquated γ′ in weld heat affected zone (HAZ) of Inconel 738LC superalloy. Scripta Mater 51(2):141–146. https://doi.org/10.1016/j.scriptamat.2004.03.040

    Article  Google Scholar 

  11. 11.

    Cloots M, Uggowitzer PJ, Wegener K (2016) Investigations on the microstructure and crack formation of IN738LC samples processed by selective laser melting using Gaussian and doughnut profiles. Mater Des 89:770–784. https://doi.org/10.1016/j.matdes.2015.10.027

    Article  Google Scholar 

  12. 12.

    Engeli R, Etter T, Hoevel S, Wegener K (2016) Processability of different IN738LC powder batches by selective laser melting. J Mater Process Technol 229:484–491

    Article  Google Scholar 

  13. 13.

    Rickenbacher L, Etter T, Hövel S, Wegener K (2013) High temperature material properties of IN738LC processed by selective laser melting (SLM) technology. Rapid Prototyp J 19(4):282–290

    Article  Google Scholar 

  14. 14.

    Risse J, Golebiewski C, Meiners W, Wissenbach K (2013) Einfluss der Prozessführung auf die Rissbildung in mittels SLM hergestellten Bauteilen aus der Nickelbasislegierung IN738LC. In: Proceedings of the RapidTech 2013. Presented at the RapidTech 2013—Trade Fair and User’s Conference for Rapid Technology

  15. 15.

    Cloots M (2017) Empirische und simulative studie über die Verarbeitbarkeit von IN738LC mittels SLM. ETH Zurich, Zurich

    Google Scholar 

  16. 16.

    Geddes B, Leon H, Huang X (2010) Superalloys: alloying and performance. ASM International, Russell

    Google Scholar 

  17. 17.

    INCO Technical Data on Alloy IN-738 (1981) The International Nickel Company, New York

  18. 18.

    Chou R, Milligan J, Paliwal M, Brochu M (2015) Additive manufacturing of Al-12Si alloy via pulsed selective laser melting. JOM 67(3):590–596. https://doi.org/10.1007/s11837-014-1272-9

    Article  Google Scholar 

  19. 19.

    Chou R, Ghosh A, Chou S, Paliwal M, Brochu M (2017) Microstructure and mechanical properties of Al10SiMg fabricated by pulsed laser powder bed fusion. Mater Sci Eng A 689:53–62

    Article  Google Scholar 

  20. 20.

    Tian Y, Muñiz Lerma JA, Brochu M (2017) Nickel-based superalloy microstructure obtained by pulsed laser powder bed fusion. Mater Charact 131:306–315. https://doi.org/10.1016/j.matchar.2017.07.024

    Article  Google Scholar 

  21. 21.

    Chou SC, Trask M, Danovitch J, Wang XL, Choi JP, Brochu M (2018) Pulsed laser powder bed fusion additive manufacturing of A356. Mater Charact. https://doi.org/10.1016/j.matchar.2018.02.004

    Google Scholar 

  22. 22.

    Gontcharov A, Liburdi J, Lowden P, Nagy D, Patel N (2014) Self healing fusion welding technology. (45752):V006T022A013. https://doi.org/10.1115/GT2014-26412

  23. 23.

    Tian Y, Gauvin R, Brochu M (2016) Microstructure evolution and rapid solidification behavior of blended nickel-based superalloy powders fabricated by laser powder deposition. Metall Mater Trans A 47(7):3771–3780. https://doi.org/10.1007/s11661-016-3505-8

    Article  Google Scholar 

  24. 24.

    Tian Y, Gontcharov A, Gauvin R, Lowden P, Brochu M (2016) Effect of heat treatments on microstructure evolution and mechanical properties of blended nickel-based superalloys powders fabricated by laser powder deposition. Mater Sci Eng A 674:646–657. https://doi.org/10.1016/j.msea.2016.07.116

    Article  Google Scholar 

  25. 25.

    Tian Y, Gontcharov A, Gauvin R, Lowden P, Brochu M (2017) Effect of heat treatment on microstructure evolution and mechanical properties of Inconel 625 with 0.4 wt% boron modification fabricated by gas tungsten arc deposition. Mater Sci Eng A 684:275–283. https://doi.org/10.1016/j.msea.2016.12.038

    Article  Google Scholar 

  26. 26.

    Tian Y, Ouyang B, Gontcharov A, Gauvin R, Lowden P, Brochu M (2017) Microstructure evolution of Inconel 625 with 0.4 wt% boron modification during gas tungsten arc deposition. J Alloys Compd 694:429–438. https://doi.org/10.1016/j.jallcom.2016.10.019

    Article  Google Scholar 

  27. 27.

    Schneider CA, Rasband WS, Eliceiri KW (2012) NIH Image to ImageJ: 25 years of image analysis. Nat Methods 9(7):671–675

    Article  Google Scholar 

  28. 28.

    Darvish K, Chen ZW, Phan MAL, Pasang T (2018) Selective laser melting of Co-29Cr-6Mo alloy with laser power 180–360W: cellular growth, intercellular spacing and the related thermal condition. Mater Charact 135:183–191. https://doi.org/10.1016/j.matchar.2017.11.042

    Article  Google Scholar 

  29. 29.

    Li S, Wei Q, Shi Y, Zhu Z, Zhang D (2015) Microstructure characteristics of Inconel 625 superalloy manufactured by selective laser melting. J Mater Sci Technol 31(9):946–952. https://doi.org/10.1016/j.jmst.2014.09.020

    Article  Google Scholar 

  30. 30.

    Tian Y, McAllister D, Colijn H, Mills M, Farson D, Nordin M, Babu S (2014) Rationalization of microstructure heterogeneity in INCONEL 718 builds made by the direct laser additive manufacturing process. Metall Mater Trans A 45(10):4470–4483. https://doi.org/10.1007/s11661-014-2370-6

    Article  Google Scholar 

  31. 31.

    Baker JC, Gahn JW (1969) Solute trapping by rapid solidification. Acta Metall 17(5):575–578. https://doi.org/10.1016/0001-6160(69)90116-3

    Article  Google Scholar 

  32. 32.

    Tables of Physical and Chemical Constants (2018) 4.2.1 X-ray absorption edges, characteristic X-ray lines and fluorescence yields. Kaye & Laby Online. Version 1.1. http://www.kayelaby.npl.co.uk. Accessed 4 June 2018

  33. 33.

    Smith PM, Aziz MJ (1994) Solute trapping in aluminum alloys. Acta Metall Mater 42(10):3515–3525. https://doi.org/10.1016/0956-7151(94)90483-9

    Article  Google Scholar 

  34. 34.

    Aziz M (1982) Model for solute redistribution during rapid solidification. J Appl Phys 53(2):1158–1168

    Article  Google Scholar 

  35. 35.

    Boettinger WJ, Bendersky LA, Coriell SR, Schaefer RJ, Biancaniello FS (1987) Microsegregation in rapidly solidified Ag-15 wt%Cu alloys. J Cryst Growth 80(1):17–25. https://doi.org/10.1016/0022-0248(87)90518-5

    Article  Google Scholar 

  36. 36.

    Eckler K, Cochrane RF, Herlach DM, Feuerbacher B (1991) Non-equilibrium solidification in undercooled NiB alloys. Mater Sci Eng A 133:702–705. https://doi.org/10.1016/0921-5093(91)90166-K

    Article  Google Scholar 

  37. 37.

    Aziz MJ, Tsao JY, Thompson MO, Peercy PS, White CW (1986) Solute trapping: comparison of theory with experiment. Phys Rev Lett 56(23):2489–2492

    Article  Google Scholar 

  38. 38.

    Smith PM, Reitanot R, Aziz MJ (2011) Solute trapping in metals. MRS Proc. https://doi.org/10.1557/PROC-279-749

    Google Scholar 

  39. 39.

    Aziz MJ, Kaplan T (1988) Continuous growth model for interface motion during alloy solidification. Acta Metall 36(8):2335–2347. https://doi.org/10.1016/0001-6160(88)90333-1

    Article  Google Scholar 

  40. 40.

    Nie P, Ojo OA, Li Z (2014) Numerical modeling of microstructure evolution during laser additive manufacturing of a nickel-based superalloy. Acta Mater 77:85–95. https://doi.org/10.1016/j.actamat.2014.05.039

    Article  Google Scholar 

  41. 41.

    Zhong M, Sun H, Liu W, Zhu X, He J (2005) Boundary liquation and interface cracking characterization in laser deposition of Inconel 738 on directionally solidified Ni-based superalloy. Scripta Mater 53(2):159–164. https://doi.org/10.1016/j.scriptamat.2005.03.047

    Article  Google Scholar 

  42. 42.

    Carter LN, Attallah MM, Reed RC (2012) Laser powder bed fabrication of nickel-base superalloys: influence of parameters; characterisation, quantification and mitigation of cracking. In: Proceedings of the 12th international symposium on superalloys, Champion, PA, 9–13 September 2012, pp 577–586

  43. 43.

    Parimi LL, A RG, Clark D, Attallah MM (2014) Microstructural and texture development in direct laser fabricated IN718. Mater Charact 89:102–111. https://doi.org/10.1016/j.matchar.2013.12.012

    Article  Google Scholar 

  44. 44.

    Thakur A (1997) Microstructural responses of a nickel-base cast IN-738 superalloy to a variety of pre-weld heat-treatments. The University of Manitoba, Winnipeg, Manitoba

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Mathieu Brochu.

Ethics declarations

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Muñiz-Lerma, J.A., Tian, Y., Wang, X. et al. Microstructure evolution of Inconel 738 fabricated by pulsed laser powder bed fusion. Prog Addit Manuf 4, 97–107 (2019). https://doi.org/10.1007/s40964-018-0062-2

Download citation

Keywords

  • Pulse laser powder bed fusion
  • Additive manufacturing
  • Nickel-based superalloy
  • Microstructure evolution