Home Porosity of LMD manufactured parts analyzed by Archimedes method and CT
Article
Licensed
Unlicensed Requires Authentication

Porosity of LMD manufactured parts analyzed by Archimedes method and CT

  • Angelina Marko , Julius Raute , Dorit Linaschke , Benjamin Graf and Michael Rethmeier
Published/Copyright: November 2, 2018
Become an author with De Gruyter Brill
Submit Manuscript Author Information
Materials Testing
From the journal Materials Testing Volume 60 Issue 11

Abstract

Pores in additive manufactured metal parts occur due to different reasons and affect the part quality negatively. Few investigations on the origins of porosity are available, especially for Ni-based super alloys. This paper presents a new study to examine the influence of common processing parameters on the formation of pores in parts built by laser metal deposition using Inconel 718 powder. Further, a comparison between the computed tomography (CT) and the Archimedes method was made. The investigation shows that CT is able to identify different kinds of pores and to give further information about their distribution. The identification of some pores as well as their shape can be dependent on the parameter setting of the analysis tool. Due to limited measurement resolution, CT is not able to identify correctly pores with diameters smaller than 0.1 mm, which leads to a false decrease in overall porosity. The applied Archimedes method is unable to differentiate between gas porosity and other kinds of holes like internal cracks or lack of fusion, but it delivered a proper value for overall porosity. The method was able to provide suitable data for the statistical evaluation with design of experiments, which revealed significant parameters on the formation of pores in LMD.

Kurzfassung

Das Auftreten von Poren in additiv gefertigten Teilen hat verschiedene Ursachen und beeinflusst die Qualität der Konstruktion negativ. Besonders für die Verarbeitung von Nickelsuperlegierungen ist zu den Mechanismen der Porenbildung wenig bekannt. Diese Arbeit untersucht daher den Einfluss typischer Prozessparameter auf die Porenbildung beim Laser-Pulver-Auftragschweißen (LPA) von Inconel 718. Zusätzlich wird ein Vergleich zweier Porositätsmessverfahren, der Computertomografie (CT) und der Archimedesmethode, vorgenommen. Die Untersuchung zeigt, dass das CT Aussagen über die Art, Größe und Verteilung der Poren treffen kann. Die Erkennung einiger Poren ebenso wie ihre Form kann von den gewählten Parametern des Analyse-Tools abhängen. Aufgrund der begrenzten Auflösung des CTs für Inconel 718, konnten Poren unter einem Durchmesser von 0.1 mm nicht sicher identifiziert werden, was zu einer falschen Verringerung der Gesamtporosität führte. Die Archimedesmethode hingegen ist nicht in der Lage zwischen Poren und anderen Hohlräumen wie Anbindungsfehlern oder Rissen zu unterscheiden. Allerdings liefert diese einen verlässlichen Wert für die Gesamtporosität einer Probe. Anhand der nach dem Archimedischen Verfahren ermittelten Porosität konnten mit einem zentral-zusammengesetzten Versuchsplan signifikante Prozessparameter für die Porenbildung beim LPA identifiziert werden.

*Correspondence Address M.Sc. Angelina Marko, Füge- und Beschichtungstechnik, Fraunhofer-Institut für Produktionsanlagen und Konstruktionstechnik IPK, Pascalstraße 8–9, 10587 Berlin, Germany, E-mail:

Angelina Marko, born in 1987, received her MSc degree in Production Technology from TU Berlin, Germany in 2015. After some practical experiences as quality engineer in the industry, she has been a scientist at Fraunhofer Institute for Production Systems and Design Technology IPK, Berlin, since 2016. Her research focus is on laser metal deposition and quality management.

Julius Raute, born in 1993, received his B.Eng degree in Mechanical Engineering from TH Brandenburg, Germany in 2017. He has been a scientific assistant at Fraunhofer Institute for Production Systems and Design Technology IPK, Berlin, Germanyince 2017.

Dorit Linaschke, born in 1978, received her diploma degree in Materials Science from TU Freiberg, Germany in 2002 and her MSc degree in Molecular Bioengineering from TU Dresden, Germany in 2004. She has been a scientist at Fraunhofer Institute for Material and Beam Technology IWS, Dresden, Germany since 2005. Her research focus is on printing technologies with polymers and functional materials.

Benjamin Graf, born in 1982, studied Mechanical Engineering at the Technical University Berlin, Germany with a focus on power engines and machines and received his diploma in 2010. After his studies, he started working at Fraunhofer IPK, Berlin, Germany in 2010. His technological working field comprises laser metal deposition, with its applications in wear protection, repair and additive manufacturing. He is Head of the Department for Joining Technology at Fraunhofer IPK, Berlin.

Prof. Dr.-Ing. Michael Rethmeier, born in 1972, studied Mechanical Engineering at the TU in Braunschweig, Germany. He then worked at the same university, where he received his Ph.D. in 2003 and then became project manager for production engineering and concepts at the Volkswagen AG group research. In 2007 he received his full professorship of the TU of Berlin. At the same time he became head of the division “Safety of Joined Components” at the Federal Institute for Materials Research and Testing BAM in Berlin. Additionally, he is division director of “Joining and Coating Technology” at Fraunhofer Institute for Production Systems and Design Technology IPK in Berlin.

References

1 J. A.Slotwinski, E. J.Garboczi, K. M.Hebenstreit: Porosity measurements and analysis for metal additive manufacturing process control, Journal of Research of the National Institute Standards Technology119 (2014), p. 49410.6028/jres.119.019Search in Google Scholar

2 G. K. L.Ng, A. E. W.Jarfors, G.Bi, H. Y.Zheng: Porosity formation and gas bubble retention in laser metal deposition, Applied Physics A: Materials Science & Processing97 (2009), pp. 641–64910.1007/s00339-009-5266-3Search in Google Scholar

3 A.Thompson, I.Maskery, R. K.Leach: X-ray computed tomography for additive manufacturing: A review, Measurement Science and Technology27 (2016) 10.1088/0957-0233/27/7/072001Search in Google Scholar

4 S.Nowotny: Beschichten, Reparieren und Generieren durch Präzisions-Auftragschweißen mit Laserstrahlen, Vakuum in Forschung und Praxis14 (2002), pp. 33–3710.1002/1522-2454(200202)14:1<33::AID-VIPR33>3.0.CO;2-XSearch in Google Scholar

5 V. P.Matilainen, J.Pekkarinen, A.Salminen: Weldability of additive manufactured stainless steel, Physics Procedia83 (2016), pp. 808–81710.1016/j.phpro.2016.08.083Search in Google Scholar

6 B.Graf, A.Gumenyuk, M.Rethmeier: Laser metal deposition as repair technology for stainless steel and titanium alloys, Physics Procedia39 (2012), pp. 376–38110.1016/j.phpro.2012.10.051.Search in Google Scholar

7 B.Cárcel, A.Serrano, J.Zambrano, V.Amigó, A. C.Cárcel: Laser cladding of TiAl intermetallic alloy on Ti6Al4 V. Process optimization and properties, Physics Procedia56 (2014), pp. 284–29310.1016/j.phpro.2014.08.173Search in Google Scholar

8 T.Petrat, B.Graf, A.Gumenyuk, M.Rethmeier: Laser metal deposition as repair technology for a gas turbine burner made of inconel 718, Physics Procedia83 (2016), pp. 761–76810.1016/j.phpro.2016.08.078Search in Google Scholar

9 E.Capello, D.Colombo, B.Previtali: Repairing of sintered tools using laser cladding by wire, Journal of Materials Processing Technology164–165 (2005), pp. 990–100010.1016/j.jmatprotec.2005.02.075Search in Google Scholar

10 B.Graf, S.Ammer, A.Gumenyuk, M.Rethmeier: Design of experiments for laser metal deposition in maintenance, Repair and Overhaul Applications, Procedia CIRP11 (2013), pp. 245–24810.1016/j.procir.2013.07.031Search in Google Scholar

11 K.Monroy, J.Delgado, J.Ciurana: Study of the pore formation on CoCrMo alloys by selective laser melting manufacturing process, Procedia Engineering63 (2013), pp. 361–36910.1016/j.proeng.2013.08.227Search in Google Scholar

12 W. E.Frazier: Metal additive manufacturing: A review, Journal of Materials Engineering and Performance23 (2014), pp. 1917–192810.1007/s11665-014-0958-zSearch in Google Scholar

13 S.Kaierle, A.Barroi, C.Noelke, J.Hermsdorf, L.Overmeyer, H.Haferkamp: Review on laser deposition welding: From Micro to Macro, Physics Procedia39 (2012), pp. 336–34510.1016/j.phpro.2012.10.046Search in Google Scholar

14 E. W.Reutzel, A. R.Nassar: A survey of sensing and control systems for machine and process monitoring of directed-energy, metal-based additive manufacturing, Rapid Prototyping Journal21 (2015), pp. 159–16710.1108/RPJ-12-2014-0177Search in Google Scholar

15 L.Li: Repair of directionally solidified superalloy GTD-111 by laser-engineered net shaping, Journal of Materials Science41 (2006), pp. 7886–789310.1007/s10853-006-0948-0Search in Google Scholar

16 E.Stevens, J.Toman, P.Zhang, A. C.To, M.Chmielus: Pore distribution, mechanical and compositional characterization of Inconel 718 manufactured by laser engineered net shaping, Ingenium: Undergraduate research at the Swanson School of Engineering, vol. 1 (2015). pp. 93–98Search in Google Scholar

17 B.Zheng, Y.Zhou, J. E.Smugeresky, J. M.Schoenung, E. J.Lavernia: Thermal behavior and microstructure evolution during laser deposition with laser-engineered net shaping: Part II. Experimental investigation and discussion, Metallurgical and Materials Transactions A39 (2008), pp. 2237–224510.1007/s11661-008-9566-6Search in Google Scholar

18 S.Barua, F.Liou, J.Newkirk, T.Sparks: Vision-based defect detection in laser metal deposition process, Rapid Prototyping Journal20 (2013), pp. 77–8510.1108/RPJ-04-2012-0036Search in Google Scholar

19 DIN Deutsches Institut für Normung e.V.: Undurchlässige Sintermetallwerkstoffe und Hartmetalle – Ermittlung der Dichte (ISO 3369:2006), Berlin, Beuth Verlag GmbH, 2014.Search in Google Scholar

20 A. B.Spierings, M.Schneider, R.Eggenberger: Comparison of density measurement techniques for additive manufactured metallic parts, Rapid Prototyping Journal17 (2011), pp. 380–38610.1108/13552541111156504Search in Google Scholar

21 A.Yadollahi, N.Shamsaei, S. M.Thompson, D. W.Seely: Effects of process time interval and heat treatment on the mechanical and microstructural properties of direct laser deposited 316L stainless steel, Materials Science and Engineering: A644 (2015), pp. 171–18310.1016/j.msea.2015.07.056Search in Google Scholar

22 L.De Chiffre, S.Carmignato, J. P.Kruth, R.Schmitt, A.Weckenmann: Industrial applications of computed tomography, CIRP Annals – Manufacturing Technology63 (2014), pp. 655–67710.1016/j.cirp.2014.05.011Search in Google Scholar

23 H. D.Carlton, A.Haboub, G. F.Gallegos, D. Y.Parkinson, A. A.MacDowell: Damage evolution and failure mechanisms in additively manufactured stainless steel, Materials Science and Engineering: A651 (2016), pp. 406–41410.1016/j.msea.2015.10.073Search in Google Scholar

24 S.Tammas-Williams, H.Zhao, F.Léonard, F.Derguti, I.Todd, P. B.Prangnell: XCT analysis of the influence of melt strategies on defect population in Ti-6Al-4 V components manufactured by selective electron beam melting, Materials Characterization102 (2015), pp. 47–6110.1016/j.matchar.2015.02.008Search in Google Scholar

25 S.Mondal, A.Bandyopadhyay, P. K.Pal: Application of artificial neural network for the prediction of laser cladding process characteristics at Taguchi-based optimized condition, International Journal of Advance Manufacturing Technology70 (2014), pp. 2151–215810.1007/s00170-013-5393-zSearch in Google Scholar

26 Y.Sun and M.Hao: Statistical analysis and optimization of process parameters in Ti6Al4 V laser cladding using Nd:YAG laser, Optics and Lasers in Engineering50 (2012), pp. 985–99510.1016/j.optlaseng.2012.01.018Search in Google Scholar

27 S.Saqiba, R. J.Urbanica, K.Aggarwal: Analysis of laser cladding bead morphology for developing additive manufacturing travel paths, Procedia CIRP17 (2014), pp. 824–82910.1016/j.procir.2014.01.098Search in Google Scholar

28 A.Marko, B.Graf, M.Rethmeier: Statistical analysis of weld bead geometry in Ti6Al4 V laser cladding: Comparison of central composite design and five step full factorial test plan, Materials Testing59 (2017), pp. 837–84310.3139/120.111077Search in Google Scholar

Published Online: 2018-11-02
Published in Print: 2018-11-15

© 2018, Carl Hanser Verlag, München

Articles in the same Issue

  1. Inhalt/Contents
  2. Contents
  3. Fachbeiträge/Technical Contributions
  4. Bending deformation and indentation hardness of electrochemically deposited nanocrystalline nickel-iron alloys
  5. Al-Si piston alloy behavior under combined mechanical and thermal cyclic loading with superimposed high-frequency thermal cycling
  6. Porosity of LMD manufactured parts analyzed by Archimedes method and CT
  7. Structure and mechanical properties of ADC 12 Al foam-polymer interpenetrating phase composites with epoxy resin or silicone
  8. Strength changes of 40 Cr steel subjected to cyclic torsion below the fatigue limit
  9. Auxetic aluminum sheets in lightweight structures
  10. Effect of thickness on the fracture toughness of high strength steel for gas well casings
  11. Effect of laser welding speed on the weld quality of a 5A06 aluminum alloy
  12. Correlation of ultrasound velocity with physico-mechanical properties of Jodhpur sandstone
  13. Etching behavior of ZnO:Ga thin films
  14. Repair of an aluminum plate with an elliptical hole using a composite patch
  15. Impression creep behavior of extruded ZK60 and ZK60+1 %Y magnesium alloys
  16. Experimental study for the bearing capacity calculation of concrete expanded plates in squeezed branch piles
  17. Mechanical properties and microstructure of autoclaved green UHPC blended with granite stone powders
  18. Mechanical properties and microstructure of glass carbon hybrid composites
https://doi.org/10.3139/120.111232

Articles in the same Issue

  1. Inhalt/Contents
  2. Contents
  3. Fachbeiträge/Technical Contributions
  4. Bending deformation and indentation hardness of electrochemically deposited nanocrystalline nickel-iron alloys
  5. Al-Si piston alloy behavior under combined mechanical and thermal cyclic loading with superimposed high-frequency thermal cycling
  6. Porosity of LMD manufactured parts analyzed by Archimedes method and CT
  7. Structure and mechanical properties of ADC 12 Al foam-polymer interpenetrating phase composites with epoxy resin or silicone
  8. Strength changes of 40 Cr steel subjected to cyclic torsion below the fatigue limit
  9. Auxetic aluminum sheets in lightweight structures
  10. Effect of thickness on the fracture toughness of high strength steel for gas well casings
  11. Effect of laser welding speed on the weld quality of a 5A06 aluminum alloy
  12. Correlation of ultrasound velocity with physico-mechanical properties of Jodhpur sandstone
  13. Etching behavior of ZnO:Ga thin films
  14. Repair of an aluminum plate with an elliptical hole using a composite patch
  15. Impression creep behavior of extruded ZK60 and ZK60+1 %Y magnesium alloys
  16. Experimental study for the bearing capacity calculation of concrete expanded plates in squeezed branch piles
  17. Mechanical properties and microstructure of autoclaved green UHPC blended with granite stone powders
  18. Mechanical properties and microstructure of glass carbon hybrid composites
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 5.11.2025 from https://www.degruyterbrill.com/document/doi/10.3139/120.111232/html
Scroll to top button