Skip to main content
SpringerLink
Log in

Microtomographic Analysis of Splat Formation and Layer Build-Up of a Thermally Sprayed Coating

  • Peer-Reviewed
  • Published:
Journal of Thermal Spray Technology Aims and scope Submit manuscript

Abstract

Thermal spraying is a material processing technique, which is based on the combination of thermal and kinetic energy. The used feedstock is melted in a hot flame. The melt is atomized and accelerated by means of atomization or process gases. As the formed particles hit a pre-treated substrate they are rapidly solidified and consolidate to form splats. The splats pile one-on-top-of-other forming lamellas creating the final coating. In the work presented here a combination of cored wire (WC as filling powder) and massive wire (copper) were simultaneously sprayed using the twin wire arc spraying process. 3D micro tomography was used in order to gain knowledge about splat formation and layer build-up. Due to the high attenuation coefficient of tungsten in comparison with copper and carbon, tungsten-rich particles and splats can easily be spotted in the tomogram of the coating layer. It turns out that besides irregular formed flat splats also ball-shaped particles exist in the coating layer which suggests that the spherical particles impacted on the substrate in an un-molten state. By 3D data processing tungsten-rich particles were visualized to analyze their spatial distributions and to quantify their geometric parameters. This work aims at contributing to the understanding of spraying processes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7

Similar content being viewed by others

References

  1. N.A. Hussary and J.V.R. Heberlein, Effect of System Parameters on Metal Breakup and Particle Formation in the Wire Arc Spray Process, J. Therm. Spray Technol., 2007, 16(1), p 1-13

    Article  Google Scholar 

  2. H.L. Liao, Y.L. Zhu, R. Bolot, C. Coddet, and S.N. Ma, Size Distribution of Particles from Individual Wires and the Effects of Nozzle Geometry in Twin Wire Arc Spraying, Surf. Coat. Technol., 2005, 200, p 2123-2130

    Article  CAS  Google Scholar 

  3. A.P. Newbery, P.S. Grant, and R.A. Neiser, The Velocity and Temperature of Steel Droplets During Electric Arc Spraying, Surf. Coat. Technol., 2005, 195, p 91-101

    Article  CAS  Google Scholar 

  4. M.P. Planche, H. Liao, and C. Coddet, Relationships Between In-Flight Particle Characteristics and Coating Microstructure with a Twin Wire Arc Spray Process and Different Working Conditions, Surf. Coat. Technol., 2004, 182, p 215-226

    Article  CAS  Google Scholar 

  5. A.P. Newbery, T. Rayment, and P.S. Grant, A Particle Image Velocimetry Investigation of In-Flight and Deposition Behaviour of Steel Droplets During Electric Arc Spray Forming, Mater. Sci. Eng. A, 2004, 383, p 137-145

    Article  Google Scholar 

  6. P.S. Mohanty, R. Allor, P. Lechowicz, R. Parker, and J. Craig, Particle Temperature and Velocity Characterization in Spray Tooling Process by Thermal Imaging Technique, Thermal Spray 2003: Advancing the Science and Applying the Technology, C. Moreau and B. Marple, Ed., ASM International, Materials Park, OH, 2003, p 1183-1190

    Google Scholar 

  7. I.K. Hui, M. Hau, and H.C.W. Lau, A Parametric Investigation of Arc Spraying Process for Rapid Mould Making, Int. J. Adv. Manuf. Technol., 2003, 22, p 786-795

    Article  Google Scholar 

  8. A. Pourmousa, J. Mostaghimi, A. Abdini, and S. Chandra, Particle Size Distribution in a Wire-Arc Spraying System, J. Therm. Spray Technol., 2005, 14(4), p 502-510

    Article  CAS  Google Scholar 

  9. N.A. Hussary and J.V.R. Heberlein, Atomization and Particle-Jet Interaction in the Wire-Arc Spraying Process, J. Therm. Spray Technol., 2001, 10(4), p 604-610

    Article  CAS  Google Scholar 

  10. Y.L. Zhu, H.L. Liao, C. Coddet, and B.S. Xu, Characterization Via Image Analysis of Cross-Over Trajectories and Inhomogeneity in Twin Wire Arc Spraying, Surf. Coat. Technol., 2003, 162, p 301-308

    Article  CAS  Google Scholar 

  11. W. Tillmann, E. Vogli, and M. Abdulgader, Partikelinteraktion (Cross Over) in der Flugphase beim Lichtbogenspritzen von Fülldrähten. Sonderforschungsbereich 708, 3D-Surface Engineering für Werkzeugsysteme der Blechformteilefertigung, Erzeugung, Modellierung, Bearbeitung, 2. Öffentliches Kolloquium, 21, November 2008 (Dortmund), p 43-51

  12. M. Pasandideh-Fard, “Droplet Impact and Solidification in a Thermal Spray Process,” Dissertation of Mechanical and Industrial Engineering, University of Toronto, 1998

  13. J. Wilden, A. Wank, and F. Schreiber, Wires for Arc- and High Velocity Flame Spraying—Wire Design, Materials and Coatings Properties, Thermal Spray: Surface Engineering via Applied Research, C.C. Berndt, Ed. (Montréal, QC, Canada), ASM International, Materials Park, OH, USA, 2000, p 609-617

  14. P. Ctibor, R. Lechnerova, and V. Benes, Quantitative Analysis of Pores of Two Types in a Plasma-Sprayed Coating, Mater. Charact., 2006, 56, p 297-304

    Article  CAS  Google Scholar 

  15. V. Guipont, G. Rolland, M. Jeandin, C. Peyrega, D. Jeulin, and W. Ludwig, Microstructures of Cold-Sprayed Coatings Investigated by X-Ray Microtomography, Therm. Spray Bull., 2010, 2, p 140-147

    Google Scholar 

  16. A. Kulkarni, S. Sampath, A. Goland, H. Herman, and B. Dowd, Computed Microtomography Studies to Characterize Microstructure Property Correlations in Thermal Sprayed Alumina Deposits, Scripta Mater., 2000, 43, p 471-476

    Article  CAS  Google Scholar 

  17. J. Ilavsky, Characterization of Complex Thermal Barrier Deposits Pore Microstructures by a Combination of Imaging, Scattering, and Intrusion Techniques, J. Therm. Spray Technol., 2010, 19, p 178-189

    Article  Google Scholar 

  18. L.A. Feldkamp, L.C. Davis, and J.W. Kress, Practical Cone Beam Algorithm, J. Opt. Soc. Am. A, 1984, 1, p 612-619

    Article  Google Scholar 

Download references

Acknowledgment

The authors gratefully acknowledge the financial support of the DFG (German Science Foundation) within the Collaborative Research Center SFB 708 TP/B3.

Author information

Authors and Affiliations

  1. Institute of Materials Engineering, Faculty of Mechanical Engineering, Technische Universität Dortmund, Leonhard-Euler-Str. 2, 44227, Dortmund, Germany

    W. Tillmann & M. Abdulgader

  2. Dortmunder Initiative zur rechnerintegrierten Fertigung (RIF) e.V, Joseph-von-Fraunhofer-Str. 20, 44227, Dortmund, Germany

    J. Nellesen

Authors
  1. W. Tillmann
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. J. Nellesen
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. M. Abdulgader
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to J. Nellesen.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Tillmann, W., Nellesen, J. & Abdulgader, M. Microtomographic Analysis of Splat Formation and Layer Build-Up of a Thermally Sprayed Coating. J Therm Spray Tech 21, 514–521 (2012). https://doi.org/10.1007/s11666-012-9737-2

Download citation

  • Received:

  • Revised:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11666-012-9737-2

Keywords

Search

Navigation