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Author Golosy, I. O. ♦ Tsipas, S. A. ♦ Clyne, T. W.
Source SpringerLink
Content type Text
Publisher Springer-Verlag
File Format PDF
Copyright Year ©2005
Language English
Subject Domain (in DDC) Natural sciences & mathematics ♦ Chemistry & allied sciences ♦ Technology ♦ Engineering & allied operations
Subject Keyword heat transfer ♦ modeling ♦ plasma spaying ♦ thermal barrier coatings ♦ thermal conductivity ♦ Surfaces and Interfaces, Thin Films ♦ Tribology, Corrosion and Coatings ♦ Materials Science ♦ Characterization and Evaluation of Materials ♦ Operating Procedures, Materials Treatment ♦ Analytical Chemistry
Abstract Numerical (finite difference) and analytical models have been developed for the simulation of heat flow through plasma-sprayed coatings, allowing the effective thermal conductivity to be predicted as a function of microstructural parameters. The structure is assumed to be composed of lamellar material (splats), separated by (thin) pores, within which there are areas of contact (bridges). The analytical model is based on dividing the material into two regimes, within which the heat flow occurs either by unidirectional serial flow through lamellae and pores or by being funneled through the regions of the lamellae above and below the bridges. The validity of this model is demonstrated by a comparison of the predictions obtained from it and those obtained from the numerical model. The effects of pore geometry on conductive and radiative heat transfer within the coating have been investigated over a range of temperatures and gas pressures. It is shown that the main factor controlling the conductivity is the intersplat bridge area. Comparisons are also presented with experimental conductivity data, for cases in which some attempt has been made to characterize the key microstructural features. The study is oriented toward thermal barrier coatings, based on zirconiayttria top coats. It is noted that the effect of microstructural sintering, which tends to occur in these coatings under service conditions, can be predicted using this model.
ISSN 10599630
Age Range 18 to 22 years ♦ above 22 year
Educational Use Research
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2005-01-01
Publisher Place New York
e-ISSN 15441016
Journal Journal of Thermal Spray Technology
Volume Number 14
Issue Number 2
Page Count 10
Starting Page 205
Ending Page 214


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Source: SpringerLink