Residual Stresses in Selective Laser Melted Samples of a Nickel Based Superalloy
A. Kromm, S. Cabeza, T. Mishurova, N. Nadammal, T. Thiede, G. Bruno
download PDFAbstract. Additive Manufacturing (AM) through the Selective Laser Melting (SLM) route offers ample scope for producing geometrically complex parts compared to the conventional subtractive manufacturing strategies. Nevertheless, the residual stresses which develop during the fabrication can limit application of the SLM components by reducing the load bearing capacity and by inducing unwanted distortion, depending on the boundary conditions specified during manufacturing. The present study aims at characterizing the residual stress states in the SLM parts using different diffraction methods. The material used is the nickel based superalloy Inconel 718. Microstructure as well as the surface and bulk residual stresses were characterized. For the residual stress analysis, X-ray, synchrotron and neutron diffraction methods were used. The measurements were performed at BAM, at the EDDI beamline of -BESSY II synchrotron- and the E3 line -BER II neutron reactor- of the Helmholtz-Zentrum für Materialien und Energie (HZB) Berlin. The results reveal significant differences in the residual stress states for the different characterization techniques employed, which indicates the dependence of the residual state on the penetration depth in the sample. For the surface residual stresses, longitudinal and transverse stress components from X-ray and synchrotron agree well and the obtained values were around the yield strength of the material. Furthermore, synchrotron mapping disclosed gradients along the width and length of the sample for the longitudinal and transverse stress components. On the other hand, lower residual stresses were found in the bulk of the material measured using neutron diffraction. The longitudinal component was tensile and decreased towards the boundary of the sample. In contrast, the normal component was nearly constant and compressive in nature. The transversal component was almost negligible. The results indicate that a stress re-distribution takes place during the deposition of the consecutive layers. Further investigations are planned to study the phenomenon in detail.
Keywords
Additive Manufacturing, Selective Laser Melting, Residual Stresses
Published online 9/11/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: A. Kromm, S. Cabeza, T. Mishurova, N. Nadammal, T. Thiede, G. Bruno, ‘Residual Stresses in Selective Laser Melted Samples of a Nickel Based Superalloy’, Materials Research Proceedings, Vol. 6, pp 259-264, 2018
DOI: http://dx.doi.org/10.21741/9781945291890-41
The article was published as article 41 of the book Residual Stresses 2018
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
References
[1] L.E. Murr, S.M. Gaytan, D.A. Ramirez, E. Martinez, J. Hernandez, K.N. Amato, P.W. Shindo, F.R. Medina, R.B. Wicker, Metal Fabrication by Additive Manufacturing Using Laser and Electron Beam Melting Technologies, J Mater Sci Technol 28(1) (2012) 1-14. https://doi.org/10.1016/S1005-0302(12)60016-4
[2] K.N. Amato, S.M. Gaytan, L.E. Murr, E. Martinez, P.W. Shindo, J. Hernandez, S. Collins, F. Medina, Microstructures and mechanical behavior of Inconel 718 fabricated by selective laser melting, Acta Mater 60(5) (2012) 2229-2239. https://doi.org/10.1016/j.actamat.2011.12.032
[3] P. Mercelis, J.P. Kruth, Residual stresses in selective laser sintering and selective laser melting, Rapid Prototyping J 12(5) (2006) 254-265. https://doi.org/10.1108/13552540610707013
[4] C.E. Protasov, V.A. Safronov, D.V. Kotoban, A.V. Gusarov, Experimental study of residual stresses in metal parts obtained by selective laser melting, Laser Assisted Net Shape Engineering 9 International Conference on Photonic Technologies Proceedings of the Lane 2016 83 (2016) 825-832.
[5] L. Van Belle, G. Vansteenkiste, J.C. Boyer, Investigation of residual stresses induced during the selective laser melting process, Key Eng Mater 554-557 (2013) 1828-1834. https://doi.org/10.4028/www.scientific.net/KEM.554-557.1828
[6] M.S. Abdul Aziz, T. Furumoto, K. Kuriyama, S. Takago, S. Abe, A. Hosokawa, T. Ueda, Residual Stress and Deformation of Consolidated Structure Obtained by Layered Manufacturing Process, J Adv Mech Des Syst 7(2) (2013) 244-256. https://doi.org/10.1299/jamdsm.7.244
[7] T. Mishurova, S. Cabeza, T. Thiede, N. Nadammal, A. Kromm, M. Klaus, C. Genzel, C. Haberland, G. Bruno, The Influence of the Support Structure on Residual Stress and Distortion in SLM Inconel 718 Parts, Metallurgical and Materials Transactions A (2018).
[8] N. Nadammal, A. Kromm, R. Saliwan-Neumann, L. Farahbod, C. Haberland, P. Portella, Influence of Support Configurations on the Characteristics of Selective Laser-Melted Inconel 718, Jom-Us 70(3) (2018) 343-348. https://doi.org/10.1007/s11837-017-2703-1
[9] B. Chong, S. Shrestha, Y.K. Chou, Stress and Deformation Evaluations of Scanning Strategy Effect in Selective Laser Melting, Proceedings of the Asme 11th International Manufacturing Science and Engineering Conference, 2016, Vol 3 (2016). https://doi.org/10.1115/MSEC2016-8819
[10] Y. Liu, Y.Q. Yang, D. Wang, A study on the residual stress during selective laser melting (SLM) of metallic powder, Int J Adv Manuf Tech 87(1-4) (2016) 647-656. https://doi.org/10.1007/s00170-016-8466-y
[11] Y.J. Lu, S.Q. Wu, Y.L. Gan, T.T. Huang, C.G. Yang, J.J. Lin, J.X. Lin, Study on the microstructure, mechanical property and residual stress of SLM Inconel-718 alloy manufactured by differing island scanning strategy, Opt Laser Technol 75 (2015) 197-206. https://doi.org/10.1016/j.optlastec.2015.07.009
[12] N. Nadammal, S. Cabeza, T. Mishurova, T. Thiede, A. Kromm, C. Seyfert, L. Farahbod, C. Haberland, J.A. Schneider, P.D. Portella, G. Bruno, Effect of hatch length on the development of microstructure, texture and residual stresses in selective laser melted superalloy Inconel 718, Mater Design 134 (2017) 139-150. https://doi.org/10.1016/j.matdes.2017.08.049
[13] M. Shiomi, K. Osakada, K. Nakamura, T. Yamashita, F. Abe, Residual stress within metallic model made by selective laser melting process, Cirp Ann-Manuf Techn 53(1) (2004) 195-198. https://doi.org/10.1016/S0007-8506(07)60677-5
[14] J.P. Kruth, J. Deckers, E. Yasa, R. Wauthle, Assessing and comparing influencing factors of residual stresses in selective laser melting using a novel analysis method, P I Mech Eng B-J Eng 226(B6) (2012) 980-991.
[15] C. Genzel, C. Stock, W. Reimers, Application of energy-dispersive diffraction to the analysis of multiaxial residual stress fields in the intermediate zone between surface and volume, Mat Sci Eng a-Struct 372(1-2) (2004) 28-43. https://doi.org/10.1016/j.msea.2003.09.073
[16] E. Macherauch, P. Müller, Das sin²ψ – Verfahren der röntgenografischen Spannungsmessung, Zeitschrift für angewandte Physik 13 (1961) 305-312.
[17] C. Genzel, I.A. Denks, J. Gibmeler, M. Klaus, G. Wagener, The materials science synchrotron beamline EDDI for energy-dispersive diffraction analysis, Nucl Instrum Meth A 578(1) (2007) 23-33. https://doi.org/10.1016/j.nima.2007.05.209
[18] T. Poeste, R.C. Wimpory, R. Schneider, The new and upgraded neutron instruments for material science at HMI – current activities in cooperation with industry, Residual Stresses Vii 524-525 (2006) 223-228. https://doi.org/10.4028/0-87849-414-6.223
