Enhanced drilling process to improve hole quality of additively manufactured Inconel 718 Alloy
Ozhan Kitay, Yusuf Kaynak, Aqib Mashood Khan
Abstract. Post-processing plays a critical role considering the product fabricated by additive manufacturing process. The hole produced in the additively manufactured products requires additional attention in terms of surface and subsurface quality. In this study, drilling was applied to improve the hole quality of Inconel 718 alloy manufactured by powder bed fusion-laser beam (PBF-LB) method. Inconel 718 alloy manufactured under different PBF-LB process parameters was drilled with sharp corner, radius corner, and chamfer corner drill bits. The measured outputs were the surface quality of drilled hole, surface topography, surface and subsurface microhardness. This study showed that drilling process helps to improve the surface quality of additively manufactured Inconel 718 by reducing the surface roughness. Depending on the geometry of cutting edge of drill bit used in drilling operation, it is possible to improve surface quality by 90% comparing to the as built quality.
Keywords
Additive Manufacturing, Inconel 718, Drilling, Surface Quality, Microhardness
Published online 5/7/2025, 10 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Ozhan Kitay, Yusuf Kaynak, Aqib Mashood Khan, Enhanced drilling process to improve hole quality of additively manufactured Inconel 718 Alloy, Materials Research Proceedings, Vol. 54, pp 228-237, 2025
DOI: https://doi.org/10.21741/9781644903599-25
The article was published as article 25 of the book Material Forming
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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