Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/41705

Title

Thermal conductivity behavior of sol-gel post-treated thermal barrier coatings

Author(s)

Lima, C. R. C.;  Senturk, Ufuk;  Lima, Rogerio S.;  Berndt, Christopher C.

Abstract

Thermal barrier coatings have been extensively used in several industrial segments. The material used as an insulator in such systems has been partially stabilized zirconia (PSZ) plasma sprayed over a metallic bond coat layer. The ceramic layer is usually porous, thus improving insulation properties. The porosity also increases gas permeability and, therefore, reduces oxidation resistance of the coating. Post-treatments have been applied to reduce the open porosity and improve oxidation resistance. In this work thermal barrier coatings were applied on low carbon steel substrates using two sets of bond coat, i.e., metallic and metal-ceramic. The metallic bond coat was NiCrAlY. The metal-ceramic bond coat was a mixture of NiCrAlY and 8% yttria partially stabilized zirconia, which were applied by simultaneous feeding to the plasma torch from two powder feeders. A sol-gel method was employed to impregnate the porous ceramic top coat with alumina or zirconia. The samples in the as-sprayed and post-treated condition were characterized using mercury intrusion porosimetry (MIP), thermal conductivity.

Publication type

Conference paper

Source

Proceedings of the 1st International Thermal Spray Conference, 'Thermal spray surface engineering via applied research', Montreal, Quebec, Canada, 09-11 May 2000 / Christopher C. Berndt (ed.), pp. 1057-1060

Publication year

2000

Keyword(s)

Alumina;  Carbon steel;  Ceramic materials;  Functionally graded materials;  Mechanical permeability;  Metal-ceramic bond coats;  Oxidation resistance;  Plasma spraying;  Porosimeters;  Porosity;  Powders;  Sol-gels;  TBCs;  Thermal barrier coatings;  Thermal conductivity;  Yttrium;  Zirconia

Publisher

ASM International

ISBN

9780871706805, 0871706806

Peer reviewed