Citation:
J. R. Nicholls, K. J. Lawson, A. Johnstone, D. S. Rickerby, Methods to reduce the thermal conductivity of EB-PVD TBCs, Surface and Coatings Technology, Volumes 151-152, 1 March 2002, Pages 383-391
Abstract:
This paper reviews the advantages and disadvantages of various thermal barrier
coating (TBC) systems, with the aim of custom designing a TBC system to be both
strain tolerant and have a low thermal conductivity. Methods of heat transfer
within zirconia based ceramics are discussed, including the influence of coating
microstructure and ceramic composition. It is shown the addition of dopant atoms
(colouring) is effective in reducing â  phononâ  transport and that layered
microstructures are effective in reducing â  photonâ  transport. Advanced
processing, using EB-PVD coating methods has allowed both coloured and layered
ceramic coatings to be produced. Measured thermal conductivities of 1.0 W mKâ  1
have been achieved using these methods, much lower than current commercial EB-
PVD coatings at 1.5âÂ