Abstract
Additive manufacturing processes such as laser powder bed fusion (LPBF) are progressively implemented in industry due to increased flexibility and ability to produce complex geometries. However, the required dimensional and surface quality cannot be achieved even tough nearly fully dense net-shaped components are manufactured. Precision surfaces for design requirement can only be achieved with subsequent machining processes. Therefore, in this paper, milling investigations on nickel alloy Inconel 625 workpiece samples that were built using LPBF-based additive manufacturing process have been conducted. The samples were fabricated using different layer-to-layer scan strategy rotations. The side milling experiments were performed on machining of surfaces in horizontal (XY) and vertical (Z) orientations. It was observed that machining forces were influenced by the relative engagements of cutter feed direction and workpiece built directions. When milling cutter was fed against the vertical direction, lower peak forces with higher deviations were recorded. On the contrary, feeding the milling cutter along the vertical build direction resulted in higher peak forces with lower deviations. By using metal cutting principles, shear yield stress and yield strength at each milling case and relative engagements were identified. The results indicate that the yield stress is higher along the horizontal (XY) orientation and affects the milling forces and it is lower vertical (Z) build direction however, a scan strategy rotation of 90° layer-wise built provides an increase in yield strength as well as at higher cutting speeds due to strain-hardening behaviour of additively fabricated Inconel 625 material.
Similar content being viewed by others
References
M’Saoubi R, Axinte D, Soo SL, Nobel C, Attia H, Kappmeyer G, Engin S, Sim WM (2015) High performance cutting of advanced aerospace alloys and composite materials. CIRP Ann Manuf Technol 64:557–580
Jawahir IS, Brinksmeier E, M’Saoubi R, Aspinwall DK, Outeiro JC, Meyer D, Umbrello D, Jayal AD (2011) Surface integrity in material removal processes: recent advances. CIRP Ann Manuf Technol 60:603–626
Thakur A, Gangopadhyay S (2016) State-of-the-art in surface integrity in machining of nickel-based super alloys. Int J Mach Tools Manuf 100:25–54
Schmidt M, Merklein M, Bourell D, Dimitrov D, Hausotte T, Wegener K, Overmeyer L, Vollertsen F, Levy GN (2017) Laser based additive manufacturing in industry and academia. CIRP Ann Manuf Technol 66(2):561–583
Wiederkehr P, Bergmann JA (2018) An integrated macroscopic model for simulating SLM and milling processes. Prod Eng 12(3–4):465–472
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
Li D, Guo Q, Guo S, Peng H, Wu Z (2011) The microstructure evolution and nucleation mechanisms of dynamic recrystallization in hot-deformed Inconel 625 superalloy. Mater Des 32:696–705
Martin JH, Yahata BD, Hundley JM, Mayer JA, Schaedler TA, Pollock TM (2017) 3D printing of high-strength aluminium alloys. Nature 549:365–369
Arısoy YM, Criales LE, Özel T, Lane B, Moylan S, Donmez A (2017) Influence of scan strategy and process parameters on microstructure and its optimization in additively manufactured nickel alloy 625 via laser powder bed fusion. Int J Adv Manuf Technol 90:1393–1417
Deng D, Peng RL, Brodin H, Moverare J (2018) 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 713:294–306
EOS Nickel alloy IN625 material data sheet. https://dmlstechnology.com/images/pdf/EOS_NickelAlloy_IN625.pdf. Accessed 29 May 2019
Özel T, Altay A, Donmez A, Leach R (2018) Surface topography investigations on nickel alloy 625 fabricated via laser powder bed fusion. Int J Adv Manuf Technol 94(9–12):4451–4458
Kaynak Y, Tascioglu E (2018) Finish machining-induced surface roughness, microhardness and XRD analysis of selective laser melted Inconel 718 alloy. Procedia CIRP 71:500–504
Brown D, Li C, Liu ZY, Fang XY, Guo YB (2018) Surface integrity of Inconel 718 by hybrid selective laser melting and milling. J Virtual Phys Prototyp 13(1):26–31
Calleja A, Urbikain G, González H, Cerrillo I, Polvorosa R, Lamikiz A (2018) Inconel®718 superalloy machinability evaluation after laser cladding additive manufacturing process. Int J Adv Manuf Technol 97(5–8):2873–2885
Kim D, Park E, Kim N, Park H (2018) Experimental investigation on tool wear during the milling processes for the post-processing of selective laser melted Inconel 718 alloys. In: ASME international manufacturing science and engineering conference, Paper No. MSEC2018-6561, V001T01A011. https://doi.org/10.1115/msec2018-6561
Criales LE, Arısoy YM, Lane B, Moylan S, Donmez A, Özel T (2017) Laser powder bed fusion of nickel alloy 625: experimental investigations of effects of process parameters on melt pool size and shape with spatter analysis. Int J Mach Tools Manuf 121:22–36
Ali H, Ghadbeigi H, Mumtaz K (2018) Effect of scanning strategies on residual stress and mechanical properties of Selective Laser Melted Ti6Al4V. Mater Sci Eng A 712:175–187
Sandvik Coromant Company, Technical guide on heat resistance super alloys. https://www.sandvik.coromant.com/sitecollectiondocuments/downloads/global/technical%20guides/en-us/c-2920-034.pdf. Accessed 8 Sept 2019
Oxley PLB (1989) The mechanics of machining: an analytical approach to assessing machinability. Ellis Horwood Ltd., England; Halsted Press, New York
Jones RM (2009) Deformation theory of plasticity. Bull Ridge Publishing, Blacksburg
Acknowledgements
Samples were fabricated at National Institute of Standards and Technology through financial assistance number 70NANB14H227. Jixiong Fei and Guoliang Liu were visiting students and their stay was supported by the China Scholarship Council (CSC).
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Patel, K., Fei, J., Liu, G. et al. Milling investigations and yield strength calculations for nickel alloy Inconel 625 manufactured with laser powder bed fusion process. Prod. Eng. Res. Devel. 13, 693–702 (2019). https://doi.org/10.1007/s11740-019-00922-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11740-019-00922-2