Cite this article as: |
Benedikt Diepold, Nora Vorlaufer, Steffen Neumeier, Thomas Gartner, and Mathias Göken, Optimization of the heat treatment of additively manufactured Ni-base superalloy IN718, Int. J. Miner. Metall. Mater., 27(2020), No. 5, pp. 640-648. https://doi.org/10.1007/s12613-020-1991-6 |
Steffen Neumeier E-mail: steffen.neumeier@fau.de
Additive manufacturing (AM) of Ni-base superalloy components can lead to a significant reduction of weight in aerospace applications. AM of IN718 by selective laser melting results in a very fine dendritic microstructure with a high dislocation density due to the fast solidification process. The complex phase composition of this alloy, with three different types of precipitates and high residual stresses, necessitates adjustment of the conventional heat treatment for AM parts. To find an optimized heat treatment, the microstructures and mechanical properties of differently solution heat-treated samples were investigated by transmission and scanning electron microscopy, including electron backscatter diffraction, and compression tests. After a solution heat treatment (SHT), the Nb-rich Laves phase dissolves and the dislocation density is reduced, which eliminates the dendritic substructure. SHT at 930 or 954°C leads to the precipitation of the δ-phase, which reduces the volume fraction of the strengthening γ′- and γ′′-phases formed during the subsequent two stage aging treatment. With a higher SHT temperature of 1000°C, where no δ-phase is precipitated, higher γ′ and γ′′ volume fractions are achieved, which results in the optimum strength of all of the solution heat treated conditions.
[1] |
L. Nickels, AM and aerospace: An ideal combination, Met. Powder Rep., 70(2015), No. 6, p. 300. doi: 10.1016/j.mprp.2015.06.005
|
[2] |
S. Soller, R. Behr, F. Laithier, M. Lehmann, A. Preuss, and R. Salapete, Design and testing of liquid propellant injectors for additive manufacturing, [in] 7th European Conference for Aerospace Sciences, Milan, 2017, p. 306.
|
[3] |
N. Arjakine, J. Bruck, B. Grüger, D.M. Seeger, and R. Wilkenhoener, Advanced weld repair of gas turbine hot section components, [in] ASME Turob Expo 2008: Power for Land, Sea and Air, Berlin, 2008, p. 559.
|
[4] |
Q.B. Jia and D.D. Gu, elective laser melting additive manufacturing of Inconel 718 superalloy parts: Densification, microstructure and properties, J. Alloys Compd., 585(2014), p. 713. doi: 10.1016/j.jallcom.2013.09.171
|
[5] |
Y.S. Lee and W. Zhang, Modeling of heat transfer, fluid flow and solidification microstructure of nickel-base superalloy fabricated by laser powder bed fusion, Addit. Manuf., 12(2016), p. 178.
|
[6] |
N. Raghavan, R. Dehoff, S. Pannala, S. Simunovic, M. Kirka, J. Turner, N. Carlson, and S.S. Babu, Numerical modeling of heat-transfer and the influence of process parameters on tailoring the grain morphology of IN718 in electron beam additive manufacturing, Acta Mater., 112(2016), p. 303. doi: 10.1016/j.actamat.2016.03.063
|
[7] |
P. Mercelis and J.P. Kruth, Residual stresses in selective laser sintering and selective laser melting, Rapid Prototyp. J., 12(2006), No. 5, p. 254. doi: 10.1108/13552540610707013
|
[8] |
Y.P. Mei, Y.C. Liu, C.X. Liu, C. Li, L.M. Yu, Q.Y. Guo, and H.J. Li, Effect of base metal and welding speed on fusion zone microstructure and HAZ hot-cracking of electron-beam welded Inconel 718, Mater. Des., 89(2016), p. 964. doi: 10.1016/j.matdes.2015.10.082
|
[9] |
T. Raza, K. Hurtig, G. Asala, J. Andersson, L.E. Svensson, and O.A. Ojo, Influence of heat treatments on heat affected zone cracking of gas tungsten arc welded additive manufactured alloy 718, Metals, 9(2019), No. 8, p. 881. doi: 10.3390/met9080881
|
[10] |
R. Mertens, B. Vrancken, N. Holmstock, Y. Kinds, J.P. Kruth, and J. Van Humbeeck, Influence of powder bed preheating on microstructure and mechanical properties of H13 tool steel SLM parts, Phys. Procedia, 83(2016), p. 882. doi: 10.1016/j.phpro.2016.08.092
|
[11] |
B. Vrancken, S. Buls, J.P. Kruth, and J. Van Humbeeck, Preheating of selective laser melted Ti6Al4V: Microstructure and mechanical properties, [in] Proceedings of the 13th World Conference on Titanium, San Diego, 2016, p. 1269.
|
[12] |
Y. Lee, M. Nordin, S.S. Babu, and D.F. Farson, Effect of fluid convection on dendrite arm spacing in laser deposition, Metall. Mater. Trans. B, 45(2014), No. 4, p. 1520. doi: 10.1007/s11663-014-0054-7
|
[13] |
P.W. Liu, Z. Wang, Y.H. Xiao, M.F. Horstemeyer, X.Y. Cui, and L. Chen, Insight into the mechanisms of columnar to equiaxed grain transition during metallic additive manufacturing, Addit. Manuf., 26(2019), p. 22. doi: 10.1016/j.addma.2018.12.019
|
[14] |
M. Pröbstle, S. Neumeier, J. Hopfenmüller, L.P. Freund, T. Niendorf, D. Schwarze, and M. Göken, Superior creep strength of a nickel-based superalloy produced by selective laser melting, Mater. Sci. Eng. A, 674(2016), p. 299. doi: 10.1016/j.msea.2016.07.061
|
[15] |
D.Y. Zhang, W. Niu, X.Y. Cao, and Z. Liu, Effect of standard heat treatment on the microstructure and mechanical properties of selective laser melting manufactured Inconel 718 superalloy, Mater. Sci. Eng. A, 644(2015), p. 32. doi: 10.1016/j.msea.2015.06.021
|
[16] |
W.M. Tucho, P. Cuvillier, A. Sjolyst-Kverneland, and V. Hansen, Microstructure and hardness studies of Inconel 718 manufactured by selective laser melting before and after solution heat treatment, Mater. Sci. Eng. A, 689(2017), p. 220. doi: 10.1016/j.msea.2017.02.062
|
[17] |
X.Q. Ni, D.C. Kong, Y. Wen, L. Zhang, W.H. Wu, B.B. He, L. Lu, and D.X. Zhu, Anisotropy in mechanical properties and corrosion resistance of 316L stainless steel fabricated by selective laser melting, Int. J. Miner. Metall. Mater., 26(2019), No. 3, p. 319. doi: 10.1007/s12613-019-1740-x
|
[18] |
T. Vilaro, C. Colin, J.D. Bartout, L. Nazé, and M. Sennour, Microstructural and mechanical approaches of the selective laser melting process applied to a nickel-base superalloy, Mater. Sci. Eng. A, 534(2012), p. 446. doi: 10.1016/j.msea.2011.11.092
|
[19] |
Y.L. Kuo, S. Horikawa, and K. Kakehi, Effects of build direction and heat treatment on creep properties of Ni-base superalloy built up by additive manufacturing, Scripta Mater., 129(2017), p. 74. doi: 10.1016/j.scriptamat.2016.10.035
|
[20] |
E. Chlebus, K. Gruber, B. Kuźnicka, J. Kurzac, and T. Kurzynowski, Effect of heat treatment on the microstructure and mechanical properties of Inconel 718 processed by selective laser melting, Mater. Sci. Eng. A, 639(2015), p. 647. doi: 10.1016/j.msea.2015.05.035
|
[21] |
H.E. Helmer, C. Körner, and R.F. Singer, Additive manufacturing of nickel-based superalloy Inconel 718 by selective electron beam melting: Processing window and microstructure, J. Mater. Res, 29(2014), No. 17, p. 1987. doi: 10.1557/jmr.2014.192
|
[22] |
K.N. Amato, S.M. Gaytan, L.E. Murr, E. Martinez, P.W. Shindo, J. Hernandez, S. Collins, and F. Medina, Microstructures and mechanical behavior of Inconel 718 fabricated by selective laser melting, Acta Mater., 60(2012), No. 5, p. 2229. doi: 10.1016/j.actamat.2011.12.032
|
[23] |
G.A. Rao, M. Kumar, M. Srinivas, and D.S. Sarma, Effect of standard heat treatment on the microstructure and mechanical properties of hot isostatically pressed superalloy inconel 718, Mater. Sci. Eng. A, 355(2003), No. 1-2, p. 114. doi: 10.1016/S0921-5093(03)00079-0
|
[24] |
S. Raghavan, B.C. Zhang, P. Wang, C.N. Sun, M.L.S. Nai, T. Li, and J. Wei, Effect of different heat treatments on the microstructure and mechanical properties in selective laser melted INCONEL 718 alloy, Mater. Manuf. Processes, 32(2017), No. 14, p. 1588. doi: 10.1080/10426914.2016.1257805
|
[25] |
T. Antonsson and H. Fredriksson, The effect of cooling rate on the solidification of INCONEL 718, Metall. Mater. Trans. B, 36(2005), No. 1, p. 85. doi: 10.1007/s11663-005-0009-0
|
[26] |
S. Azadian, L.Y. Wei, and R. Warren, Delta phase precipitation in Inconel 718, Mater. Charact., 53(2004), No. 1, p. 7. doi: 10.1016/j.matchar.2004.07.004
|
[27] |
M. Sundararaman, P. Mukhopadhyay, and S. Banerjee, Some aspects of the precipitation of metastable intermetallic phases in INCONEL 718, Metall. Mater. Trans. A, 23(1992), No. 7, p. 2015. doi: 10.1007/BF02647549
|
[28] |
R. Cozar and A. Pineau, Morphology of y′ and y′′ precipitates and thermal stability of inconel 718 type alloys, Metall. Trans., 4(1973), No. 1, p. 47. doi: 10.1007/BF02649604
|
[29] |
H.J. Zhang, C. Li, Q.Y. Guo, Z.Q. Ma, H.J. Li, and Y.C. Liu, Improving creep resistance of nickel-based superalloy Inconel 718 by tailoring gamma double prime variants, Scripta Mater., 164(2019), p. 66. doi: 10.1016/j.scriptamat.2019.01.041
|
[30] |
M.A. Martorano and V.B. Biscuola, Columnar front tracking algorithm for prediction of the columnar-to-equiaxed transition in two-dimensional solidification, Modell. Simul. Mater. Sci. Eng., 14(2006), No. 7, p. 1225. doi: 10.1088/0965-0393/14/7/010
|
[31] |
J. Liu and A.C. To, Quantitative texture prediction of epitaxial columnar grains in additive manufacturing using selective laser melting, Addit. Manuf., 16(2017), p. 58. doi: 10.1016/j.addma.2017.05.005
|
[32] |
R. Acharya, J.A. Sharon, and A. Staroselsky, Prediction of microstructure in laser powder bed fusion process, Acta Mater., 124(2017), p. 360. doi: 10.1016/j.actamat.2016.11.018
|
[33] |
X.M. Zhao, J. Chen, X. Lin, and W.D. Huang, Study on microstructure and mechanical properties of laser rapid forming Inconel 718, Mater. Sci. Eng. A, 478(2008), No. 1-2, p. 119. doi: 10.1016/j.msea.2007.05.079
|
[34] |
D.Y. Deng, J. Moverare, R.L. Peng, and H. Söderberg, Microstructure and anisotropic mechanical properties of EBM manufactured Inconel 718 and effects of post heat treatments, Mater. Sci. Eng. A, 693(2017), p. 151. doi: 10.1016/j.msea.2017.03.085
|
[35] |
T. Thiede, S. Cabeza, T. Mishurova, N. Nadammal, A. Kromm, J. Bode, C. Haberland, and G. Bruno, Residual stress in selective laser melted Inconel 718: Influence of the removal from base plate and deposition hatch length, Mater. Perform. Charat., 7(2018), No. 4, p. 1.
|
[36] |
N. Nadammal, S. Cabeza, T. Mishurova, T. Thiede, A. Kromm, C. Seyfert, L. Farahbod, C. Haberland, J.A. Schneider, P.D. Portella, and G. Bruno, Effect of hatch length on the development of microstructure, texture and residual stresses in selective laser melted superalloy Inconel 718, Mater. Des., 134(2017), p. 139. doi: 10.1016/j.matdes.2017.08.049
|
[37] |
Y. Liu, Y.Q. Yang, and D. Wang, A study on the residual stress during selective laser melting (SLM) of metallic powder, Int. J. Adv. Manuf. Technol., 87(2016), No. 1, p. 647.
|
[38] |
J. Schneider, B. Lund, and M. Fullen, Effect of heat treatment variations on the mechanical properties of Inconel 718 selective laser melted specimens, Addit. Manuf., 21(2018), p. 248. doi: 10.1016/j.addma.2018.03.005
|
[39] |
M.D. Sangid, T.A. Book, D. Naragani, J. Rotella, P. Ravi, A. Finch, P. Kenesei, J.S. Park, H. Sharma, J. Almer, and X.H. Xiao, Role of heat treatment and build orientation in the microstructure sensitive deformation characteristics of IN718 produced via SLM additive manufacturing, Addit. Manuf., 22(2018), p. 479. doi: 10.1016/j.addma.2018.04.032
|
[40] |
Y. Desvallées, M. Bouzidi, F. Bois, and N. Beaude, Delta phase in Inconel 718: Mechanical properties and forging process requirements, [in] E.A. Loria, eds., Superalloys 718, 625, 706 and Various Derivatives, The Minerals, Metals & Materials Society, Warrendale, 1994, p. 281.
|