Investigation of the Post-Processing Heat Treatments on Hot Tensile Properties of Selectively Laser Melted IN939 Superalloy

Öz

In recent years, the Selective Laser Melting (SLM) process has become the focus of research due to its wide range of benefits and easy fabrication advantageous in the mass production of nickel-based superalloys. However, the mechanical properties of additively manufactured nickel-based superalloys are insufficient for service conditions. Therefore, heat treatment studies are necessary to achieve desired microstructures for better mechanical properties. In this concept, it is aimed to replace melt pool boundaries and to obtain more equiaxed fine grain boundaries via heat treatment studies. This study deals with the effect of post-heat treatment studies on the microstructure and mechanical properties of selectively laser-melted Inconel 939 (IN939) superalloy. As-built and heat-treated (HIP&VHT) samples were characterized via optical and electron microscopy techniques. Transition temperatures and phases were analyzed using XRD, DSC, and Thermo-Calc simulation techniques. Finally, the effect of the hot tensile test on γʹ formation and morphology in the microstructure was investigated. Overall, the study tried to provide insight into whether the post-processes are necessary for modifying microstructure and achieving optimal mechanical properties. It was observed that both HIP and VHT had a beneficial impact on the elongation in comparison to the as-built conditions. However, no noticeable differences were achieved in ultimate tensile and yield stress.

Anahtar Kelimeler

• Additive Manufacturing
• Hot Isostatic Pressing (HIP)
• Hot Tensile Testing
• Inconel 939 (IN939)
• Selective Laser Melting (SLM)
• Vacuum Heat Treatment

Kaynakça

1. [1] M. M. Kirka and P. Fernandez-Zelaia, “Additive Materials for High Temperature Applications,” in Encyclopedia of Materials: Metals and Alloys, F. G. Caballero, Ed., Oxford: Elsevier, 2022, pp. 529–536. doi: https://doi.org/10.1016/B978-0-12-819726-4.00110-1
2. [2] A. Mostafaei et al., “Additive manufacturing of nickel-based superalloys: A state-of-the-art review on process-structure-defect-property relationship,” Prog. Mater. Sci., vol. 136, p. 101108, 2023, doi: https://doi.org/10.1016/j.pmatsci.2023.101108.
3. [3] W. Song et al., “A new approach to design advanced superalloys for additive manufacturing,” Addit. Manuf., vol. 84, p. 104098, 2024, doi: https://doi.org/10.1016/j.addma.2024.104098.
4. [4] B. Wahlmann, M. Markl, and C. Körner, “A thermo-mechanical model for hot cracking susceptibility in electron beam powder bed fusion of Ni-base superalloys,” Mater. Des., vol. 237, p. 112528, 2024, doi: https://doi.org/10.1016/j.matdes.2023.112528.
5. [5] N. J. Harrison, “Selective Laser Melting of Nickel Superalloys : solidification , microstructure and material response,” 2016.
6. [6] P. Kanagarajah, F. Brenne, T. Niendorf, and H. J. Maier, “Inconel 939 processed by selective laser melting: Effect of microstructure and temperature on the mechanical properties under static and cyclic loading,” 2013. doi: 10.1016/j.msea.2013.09.025.
7. [7] Randy Bowman, “Superalloys: A Primer and History,” in Superalloys: A Primer and History, [Online]. Available: https://www.tms.org/meetings/specialty/superalloys2000/superalloyshistory.html
8. [8] M. Doi, D. Miki, T. Moritani, and T. Kozakai, “Gamma/gamma-prime microstructure formed by phase separation of gamma-prime precipitates in a Ni-Al-Ti alloy,” in Proceedings of the International Symposium on Superalloys, 2004. doi: 10.7449/2004/superalloys_2004_109_114.

9. [9] W. Philpott, M. A. E. Jepson, and R. C. Thomson, “Comparison of the effects of a conventional heat treatment between cast and selective laser melted IN939 alloy,” 2016.
10. [10] M. N. Doğu et al., “Effect of solution heat treatment on the microstructure and crystallographic texture of IN939 fabricated by powder bed fusion-laser beam,” J. Mater. Res. Technol., vol. 24, pp. 8909–8923, 2023, doi: https://doi.org/10.1016/j.jmrt.2023.0
11. [11] A. Mashhuriazar, C. Hakan Gur, Z. Sajuri, and H. Omidvar, “Effects of heat input on metallurgical behavior in HAZ of multi-pass and multi-layer welded IN-939 superalloy,” J. Mater. Res. Technol., vol. 15, pp. 1590–1603, 2021, doi: https://doi.org/10.1016/j.jmrt.2021.08.113
12. [12] S. Sui, C. Zhong, J. Chen, A. Gasser, W. Huang, and J. H. Schleifenbaum, “Influence of solution heat treatment on microstructure and tensile properties of Inconel 718 formed by high-deposition-rate laser metal deposition,” J. Alloys Compd., vol. 740, pp. 3
13. [13] J. Risse, “Additive Manufacturing of Nickel-Base Superalloy IN738LC by Laser Powder Bed Fusion,” 2019.
14. [14] S. A. Raza, O. E. Canyurt, and H. K. Sezer, “A systematic review of Inconel 939 alloy parts development via additive manufacturing process,” Heliyon, vol. 10, no. 3, p. e25506, 2024, doi: https://doi.org/10.1016/j.heliyon.2024.e25506.
15. [15] S. Banoth, C. W. Li, Y. Hiratsuka, and K. Kakehi, “The effect of recrystallization on creep properties of alloy in939 fabricated by selective laser melting process,” 2020. doi: 10.3390/met10081016.
16. [16] G. Sjöberg et al., “Evaluation of the IN 939 alloy for large aircraft engine structures,” in Proceedings of the International Symposium on Superalloys, 2004. doi: 10.7449/2004/superalloys_2004_441_450.
17. [17] A. S. Shaikh, M. Rashidi, K. Minet-Lallemand, and E. Hryha, “On as-built microstructure and necessity of solution treatment in additively manufactured Inconel 939,” Powder Metall., vol. 66, no. 1, pp. 3–11, 2023, doi: 10.1080/00325899.2022.2041787.
18. [18] T. Zou et al., “Effect of temperature on tensile behavior, fracture morphology, and deformation mechanisms of Nickel-based additive manufacturing 939 superalloy,” J. Alloys Compd., vol. 959, p. 170559, 2023, doi: https://doi.org/10.1016/j.jallcom.2023.1705
19. [19] I. Šulák, T. Babinský, A. Chlupová, A. Milovanović, and L. Náhlík, “Effect of building direction and heat treatment on mechanical properties of Inconel 939 prepared by additive manufacturing,” J. Mech. Sci. Technol., vol. 37, no. 3, pp. 1071–1076, 2023, doi: 10.1007/s12206-022-2101-7.
20. [20] D. Deng, “Additively Manufactured Inconel 718 : Microstructures and Mechanical Properties,” 2018.
21. [21] B. Zhang, H. Ding, A. C. Meng, S. Nemati, S. Guo, and W. J. Meng, “Crack reduction in Inconel 939 with Si addition processed by laser powder bed fusion additive manufacturing,” Addit. Manuf., vol. 72, p. 103623, 2023, doi: https://doi.org/10.1016/j.addma.2023.103623.
22. [22] D. Deng, R. L. Peng, H. Brodin, and J. Moverare, “Microstructure and mechanical properties of Inconel 718 produced by selective laser melting: Sample orientation dependence and effects of post heat treatments,” Mater. Sci. Eng. A, 2018, doi: 10.1016/j.msea.2017.12.043.
23. [23] J. Xu, H. Gruber, D. Deng, R. L. Peng, and J. J. Moverare, “Short-term creep behavior of an additive manufactured non-weldable Nickel-base superalloy evaluated by slow strain rate testing,” Acta Mater., vol. 179, pp. 142–157, 2019, doi: 10.1016/j.actamat.2019.08.034.
24. [24] R. Gusain, M. Dodaran, P. Gradl, N. Shamsaei, and S. Shao, “The Influence of Heat Treatments on the Microstructure and Tensile Properties of Additively Manufactured Inconel 939,” 2023.
25. [25] A. Formenti, A. Eliasson, A. Mitchell, and H. Fredriksson, “Solidification sequence and carbide precipitation in Ni-base superalloys IN718, IN625 AND IN939,” High Temp. Mater. Process., vol. 24, Jun. 2005, doi: 10.1515/HTMP.2005.24.4.239.
26. [26] M. Jahangiri, “Study on incipient melting in cast Ni base IN939 superalloy during solution annealing and its effect on hot workability,” Mater. Sci. Technol., vol. 28, pp. 1402–1413, Jun. 2012.