Internal stresses in plasma sprayed coatings
Project ID:GA106/97/0775
Provider:Czech Science Foundation
Period:Jan 01, 1997 - Dec 31, 1999
Recipient - coordinatorInstitute of Plasma Physics, Czech Academy of Sciences, Prague
Principal Investigator:Ing. Jiří Dubský, CSc.
Co-recepient(s) / PI(s):Nuclear Physics Institute of the CAS, v. v. i. -- RNDr. Miroslav Vrána, CSc.
Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University, Prague -- Prof. RNDr. Ivo Kraus, DrSc.
Co-investigators from IPPP. Chráska, J. Písačka, P. Ctibor

Aims of the project: Internal stresses arise in the plasma deposits as a result of very fast processes on the substrate after impact of melted droplets which in a very short time deform and solidify. The used experimental technique is based on measuring crystal lattice deformation by X-ray diffraction. Since the penetration depth of X-rays is small and reaches several um only, the neutron diffraction will complement the measurements. The penetration depth of neutron is practically unlimited and therefore the internal stresses gradients towards the deposit/substrate interface will be checked. A correlation of values of internal stresses with the structural builtup of deposits will be then attempted and the reliability of used methods in real structures will be tested. Finally, the effect of used technological parameters of spraying on changes of the internal stress level will be studied. The goal of this project is to measure the internal stresses in plasma sprayed coatings or plasma sprayed free-standing parts made of di

Progress/Results: Goal of the project was set internal stresses in plasma sprayed deposits and self standing parts produced mainly from ceramic materials. It has been found dependency of this stresses both on the used feedstock material and the substrate material. Along with this result has been found dependency on chosen plasma spraying method. and on the technological conditions. Obtained results were published in international journals and on the prestige international conferences deal with either plasma spraying or the analysis and the measuring stresses. Against prior plan was the solution extended by study of influence of additional stress induced by bending and on changes of deposit Young’s modulus. It was experimentally confirmed continues closing of existing cracks in the relevant direction during addition of compressive stresses and then the increasing of Young’s modulus. The results are usable on one side for chose of right residual stress measuring method and for its evaluation. On the other side is possible use the results to chose the feedstock material and spraying technology.


Vrána M., Mikula P., Lukáš P., Dubský J., Wagner V.: New Developments in Instrumentation for Strain Scanning in NPI Řež. Materials Science Forum 321/324 (2000) 338-344. [ Abstract ]

Dubský J., Kolman B., Vyšohlíd M.: Residual stresses and yuong-modulus of alumina and chromia plasma sprayed deposits. Conference Proceedings:United Thermal Spray Conference UTSC 99. Düsseldorf : Verlag für Schweiáen und Verwande Veflahren, D.V.SVerlag, 1999 - (Lugscheider, E.; Kammer, P.) s. 659-663. ISBN 3-87155-653-x.
[UTSC '99 United Thermal Spray Conference. Düsseldorf (DE), 17.03.1999-19.03.1999]

Dubský J., Kolman B., Ctibor P., Kroupa F., Ilavský J.: Structure and residual stresses in thermally sprayed steel coatings. 0-87849-833-8. In: Functionally graded materials 1998. Zuerich : ttp Trans Tech Publications ltd, 1999 - (Kaysser, W.) s. 232-237. - (Materials Science Forum.. vol.308-311(1999)).
[International Symposium on Functionally Graded Materials /5./. Dresden (DE), 26.10.1998-29.10.1998]

Kantor P., Siegl J., Neufuss K., Dubský J.: Unavové zkoušky těles s různými typy nástřiků. Metal 99 - 8. mezinárodní metalurgický veletrh a symposium. Ostrava : TANGER, s.r.o., Ostrava, 1999. s. 250-256. ISBN 80-85988-37-2.
[METAL 99 - mezinárodní metalurgický veletrh a symposium /8./. Ostrava (CZ), 11.05.1999-13.05.1999]

Matějíček J., Sampath S., Dubský J.: X-ray Residual Stress Measurements in Metallic and Ceramic Plasma Sprayed Coatings. Journal of Thermal Spray Technology 7 [4] (1998) 489-496.

Dubský J., Kolman B., Neufuss K.: Phase Composition Changes in Annealed Plasma-Sprayed Zircon-Alumina Coatings. Thermal Spray:A United Forum for Scientific and Technological Advances. Materials Park, OH : ASM International, 1998 - (Berndt, C.) s. 473-476. ISBN 0-87170-618-0.
[United Thermal Spray Conference/1./. Indianapolis (US), 15.09.1997-18.09.1997]

Dubský J., Kolman B., Buchal A.: Phase Composition changes in plasma sprayed zircon-alumina Tubes. Thermal Spray, Meeting the Challanges of the 21st Century. Materials Park, OH : ASM International, 1998 - (Coddet, C.) s. 1613-1616. ISBN 0-87170-659-8.
[International Thermal Spray Conference /15./. Nice (FR), 25.05.1998-29.05.1998]

Dubský J., Kolman B., Ctibor P., Kroupa F.: Pnutí v ocelových nastřicích. Acta Mechanica Slovaka 2 [-] (1998) 183-188.

Matějíček J., Sampath S., Dubský J.: Residual Stress Measurement in Plasma Sprayed Coatings by x-Ray Diffraction. Thermal Spray: A United Forum for Scientific and Technological Advances. Materials Park, OH : ASM International, 1998 - (Berndt, C.) s. 855-860. ISBN 0-87170-618-0.
[United Thermal Spray Conference /1./. Indianapolis (US), 15.09.1997-18.09.1997]