Journal of Thermal Spray Technology

, Volume 20, Issue 4, pp 782–790 | Cite as

Coanda-Assisted Spray Manipulation Collar for a Commercial Plasma Spray Gun

  • K. Mabey
  • B. L. Smith
  • G. Whichard
  • T. McKechnie
Peer Reviewed


A Coanda-assisted Spray Manipulation (CSM) collar was retrofitted to a Praxair SG-100 plasma spray gun. The CSM device makes it possible to change the direction of (vector) the plasma jet and powder without moving the gun. The two-piece retrofit device replaces the standard faceplate. Two separate collars were tested: one designed for small vector angles and one for larger vector angles. It was demonstrated that the small-angle device could modify the trajectory of zirconia powder up to several degrees. Doing so could realign the plasma with the powder resulting in increased powder temperature and velocity. The large-angle device was capable of vectoring the plasma jet up to 45°. However, the powder did not vector as much. Under large-angle vectoring, the powder velocity and temperature decreased steadily with vector angle. Both devices were tested using a supersonic configuration to demonstrate that CSM is capable of vectoring supersonic plasmas.


control flow flame spray plasma alignment plasma spray spray steering trajectory vector angle 


  1. 1.
    C.C. Berndt and S.H. Leigh, Evaluation of Off-Angle Thermal Spray, Surf Coat. Technol., 1997, 89, p 213-224CrossRefGoogle Scholar
  2. 2.
    J. Ilvasky, A. Allen, G. Long, and S. Krueger, Influence of Spray Angle on the Pore and Crack Microstructure of Plasma-Sprayed Deposits, J. Am. Ceram. Soc., 1997, 80(3), p 733-742CrossRefGoogle Scholar
  3. 3.
    A. Hasui, S. Kitahara, and T. Fukushima, On Relation Between Properties of Coating and Spraying angle in Plasma Jet Spraying, Trans. Nat. Res. Inst. Met., 1970, 12(1), p 9-20Google Scholar
  4. 4.
    S. Kitahara and A. Hasui, A Study of the Bonding Mechanism of Sprayed Coatings, J. Vac. Sci. Technol., 1974, 11(4), p 747-753CrossRefGoogle Scholar
  5. 5.
    L. An, Y. Gao, and T. Zhang, Effect of Powder Injection Location on Ceramic Coatings Properties When Using Plasma Spray, J. Therm. Spray Technol., 2007, 16(5-6), p 967-973CrossRefGoogle Scholar
  6. 6.
    H. Li and X. Chen, Three-Dimensional Simulation of a Plasma Jet With Transverse Particle and Carrier Gas Injection, Thin Solid Films, 2001, 390(1-2), p 175-180CrossRefGoogle Scholar
  7. 7.
    D. Allen and B.L. Smith, Axisymmetric Coanda-Assisted Vectoring, Exp. Fluids, 2009, 46(1), p 55-64CrossRefGoogle Scholar
  8. 8.
    M. Raffel, C. Willert, S. Werely, and J. Kompenhans, Particle Image Velocimetry: A Practical Guide, Springer, Berlin, 2007Google Scholar
  9. 9.
    Utah State University, EFDL Website,
  10. 10.

Copyright information

© ASM International 2011

Authors and Affiliations

  • K. Mabey
    • 1
  • B. L. Smith
    • 1
  • G. Whichard
    • 2
  • T. McKechnie
    • 3
  1. 1.Department of Mechanical EngineeringUtah State UniversityLoganUSA
  2. 2.Technology Commercialization OfficeUtah State UniversityLoganUSA
  3. 3.Plasma Processes Inc.HuntsvilleUSA

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