Laser Welding of Laser Powder Bed Fusion Manufactured Inconel 718: Microstructure and Mechanical Properties

Abstract:

This paper focuses on the laser weldability of additively manufactured (AM) Inconel 718. The experiments of this research were conducted on different series of AM Inconel 718 alloy, i.e. as­-built, heat­ treated (HT), and HT after welding, and comprehensively characterized using optical microscope and electron back scattering diffraction (EBSD). The weld morphology and microstruc­tural evolution of the fusion zone were recorded. The mechanical properties of the welded AM Inconel 718 were evaluated by tensile tests and hardness measurements. It was found that solidification crack and micropore defects are induced in the as­built AM Inconel 718. However, defect­free weld was promoted in the HT alloy. The changes in hardness profiles and tensile strength under the experimen­tal parameters were further reported. Homogenous hardness of 500 HV across the weld was obtained when HT was applied after the LW.

• Periodical: Key Engineering Materials (Volume 883)
• Pages: 234-241
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.883.234
• Online since: April 2021
• Authors: Timo Rautio*, Jarmo Mäkikangas, Jani Kumpula, Antti Järvenpää, Atef Saad Hamada
• Keywords: Additive Manufacturing, Inconel 718, Laser Powder Bed Fusion, Laser Welding

References

[1] J. Draxler, J. Edberg, J. Andersson, and L.-E. Lindgren, Modeling and simulation of weld solidification cracking part iii,, Welding in the World, vol. 63, no. 6, (2019).

DOI: 10.1007/s40194-019-00784-3

[2] M. Donachie, Superalloys : a technical guide. Materials Park, OH: ASM International, (2002).

[3] V. Popovich, E. Borisov, A. Popovich, V. Sufiiarov, D. Masaylo, and L. Alzina, Impact of heat treatment on mechanical behaviour of inconel 718 processed with tailored microstructure by selective laser melting,, Materials & Design, vol. 131, pp.12-22, oct (2017).

DOI: 10.1016/j.matdes.2017.05.065

[4] E. Karayel and Y. Bozkurt, Additive manufacturing method and different welding applications," Journal of Materials Research and Technology, vol. 9, no. 5, pp.11-438, sep 2020.[5] J. Hong, J. Park, N. Park, I. Eom, M. Kim, and C. Kang, "Microstructures and mechanical properties of inconel 718 welds by CO2 laser welding,, Journal of Materials Processing Technology, vol. 201, no. 1-3, pp.515-520, may (2008).

DOI: 10.1016/j.jmatprotec.2007.11.224

[6] T. Jokisch, A. Marko, S. Gook, Ömer Üstündag, A. Gumenyuk, and M. Rethmeier, Laser welding of SLM-manufactured tubes made of IN625 and IN718,, Materials, vol. 12, no. 18, p.2967, sep (2019).

DOI: 10.3390/ma12182967

[7] T. Rautio, J. Mäkikangas, M. Jaskari, M. Keskitalo, and A. Järvenpää, Microstructure and mechanical properties of laser welded 316l SLM parts,, Key Engineering Materials, vol. 841, pp.306-311, may (2020).

DOI: 10.4028/www.scientific.net/kem.841.306

[8] T. Rautio, A. Hamada, J. Mäkikangas, M. Jaskari, and A. Järvenpää, Laser welding of selective laser melted ti6al4v: Microstructure and mechanical properties,, Materials Today: Proceedings, vol. 28, pp.907-911, (2020).

DOI: 10.1016/j.matpr.2019.12.322

[9] T. Rautio, A. Hamada, J. Kumpula, A. Järvenpää, and T. Allam, Enhancement of electrical conductivity and corrosion resistance by silver shell�copper core coating of additively manufactured AlSi10mg alloy,, Surface and Coatings Technology, vol. 403, p.126426, dec (2020).

DOI: 10.1016/j.surfcoat.2020.126426

[10] 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,, Materials Science and Engineering: A, vol. 713, pp.294-306, jan (2018).

DOI: 10.1016/j.msea.2017.12.043

[11] E. M. Fayed, D. Shahriari, M. Saadati, V. Brailovski, M. Jahazi, and M. Medraj, Influence of homogenization and solution treatments time on the microstructure and hardness of inconel 718 fabricated by laser powder bed fusion process,, Materials, vol. 13, no. 2574, p.2574, jun (2020).

DOI: 10.3390/ma13112574

[12] R. Vikram, A. Singh, and S. Suwas, Effect of heat treatment on the modification of microstructure of selective laser melted (SLM) IN718 and its consequences on mechanical behavior,, Journal of Materials Research, vol. 35, no. 15, pp.1949-1962, jun (2020).

DOI: 10.1557/jmr.2020.129

[13] D. Zhang, W. Niu, X. Cao, and Z. Liu, Effect of standard heat treatment on the microstructure and mechanical properties of selective laser melting manufactured inconel 718 superalloy,, Materials Science and Engineering: A, vol. 644, pp.32-40, 2015. [Online]. Available: http://www.sciencedirect.com/science/article/pii/S0921509315300745.

DOI: 10.1016/j.msea.2015.06.021

[14] H. Xiao, P. Xie, M. Cheng, and L. Song, Enhancing mechanical properties of quasi-continuouswave laser additive manufactured inconel 718 through controlling the niobium-rich precipitates,, vol. 34, p.101278, (2020).

DOI: 10.1016/j.addma.2020.101278

[15] Y.-J. Kang, S. Yang, Y.-K. Kim, B. AlMangour, and K.-A. Lee, Effect of post-treatment on the microstructure and high-temperature oxidation behaviour of additively manufactured inconel 718 alloy,, vol. 158, p.108082, (2019).

DOI: 10.1016/j.corsci.2019.06.030

[16] E. Hosseini and V. A. Popovich, A review of mechanical properties of additively manufactured inconel 718,, vol. 30, p.100877, (2019).

DOI: 10.1016/j.addma.2019.100877