Journal of Thermal Spray Technology

, Volume 8, Issue 3, pp 427–432 | Cite as

Flattening mechanism in thermal sprayed nickel particle impinging on flat substrate surface

  • M. Fukumoto
  • Y. Huang


The transition behavior of the splat pattern of nickel particles sprayed onto a flat substrate was investigated. Auger analysis and scanning electron microscopy observation of splats on a gold-coated substrate were examined. It was confirmed that splashing was not formed by flowing on the substrate surface from the impingement center to the periphery, but by jetting away from central disk. The etched splat surface revealed that the bottom part of the central disk of the splat solidified quite rapidly just after impingement onto the cold substrate. The splash pattern was found only in a direction perpendicular to the scratch pattern on the substrate. Therefore, it was confirmed that splashing was caused by some deterrent to the liquid flow, for example, due to effects such as poor wettability at the flow tip or initial rapid solidification of the splat. The drastic change of the splat pattern near the transition temperature seems to occur when the We number of the liquid flow coincides with some critical value.


disk splat flattening splash splat substrate temperature thermal sprayed particle transition temperature 


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  1. 1.
    J. Madjeski, Solidification of Droplets on a Cold Surface, Int. J. Heat Mass Transfer, Vol 19, 1976, p 1009–1013CrossRefADSGoogle Scholar
  2. 2.
    H. Fukanuma, A Porosity Formation and Flattening Model of an Impinging Molten Particle in Thermal Spray Coatings, J. Therm. Spray Technol., Vol 3 (No. 1), 1994, p 33–44Google Scholar
  3. 3.
    M. Pasandideh-Fard and J. Mostaghimi, On the Spreading and Solidification of Molten Particles in a Plasma Spray Process: Effect of Thermal Contact Resistance, Plasma Chem. Plasma Process., Vol 16 (No. 1), 1996, p 83–98CrossRefGoogle Scholar
  4. 4.
    H. Liu, E.J. Lavernia, and R.H. Rangel, Numerical Investigation of Micropore Formation during Substrate Impact of Molten Droplets in Plasma Spray Processes, Atomization and Sprays, Vol 4, 1994, p 369–384Google Scholar
  5. 5.
    M. Fukumoto, S. Katoh, T. Ohwatari, and Y. Huang, Splatting and Solidification Behavior of Plasma Sprayed Metallic Powders Impinging on Flat SUS304 Substrate, J. Jpn. Inst. Met., Vol 59 (No. 11), 1995, p 1178–1184 (in Japanese)Google Scholar
  6. 6.
    M. Fukumoto, S. Katoh, and I. Okane, Splat Behavior of Plasma Sprayed Particles on Flat Substrate Surface, Thermal Spraying-Current Status and Future Trends, Proc. Int. Thermal Spray Conf., A. Ohmori, Ed., Vol 1, 1995, p 353–358Google Scholar
  7. 7.
    Y. Huang, M. Ohwatari, and M. Fukumoto, Effect of Substrate Material on Flattening Behavior of Plasma Sprayed Nickel Particles, The Role of Welding Science and Technology in the 21st Century, Proc. Int. Symp. Japan Welding Soc., M. Ushio, Ed., Vol 2, 1996, p 731–736Google Scholar
  8. 8.
    C. Moreau, P. Gougeon, and M. Lamontagne, Influence of Substrate Preparation on the Flattening and Cooling of Plasma-Sprayed Particles, J. Therm. Spray Technol., Vol 4 (No. 1), 1995, p 25–33Google Scholar
  9. 9.
    M. Fukumoto, H. Hayashi, and T. Yokoyama, Relationship between Particle’s Splat Pattern and Coating Adhesive Strength of HVOF Sprayed Cu-Alloy, J. Japan Therm. Spray Soc., Vol 32 (No. 3), 1995, p 149–156 (in Japanese)Google Scholar
  10. 10.
    K. Nogi, N. Iwamoto, and K. Ogino, Wetting Mechanism of Ceramics by Liquid Metals, Bull. Jpn. Inst. Met., Vol 31 (No. 4), 1992, p 278–281 (in Japanese)Google Scholar
  11. 11.
    S. Inada and W-J. Yang, Solidification of Molten Metal Droplets Impinging on a Cold Surface, Exp. Heat Trans., Vol 7 (No. 2), 1994, p 93–100Google Scholar

Copyright information

© ASM International 1999

Authors and Affiliations

  • M. Fukumoto
    • 1
  • Y. Huang
    • 1
  1. 1.Dept. of Production Systems EngineeringToyohashi University of TechnologyAichiJapan

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