This paper summarizes the basic properties of ceramic materials for thermal barrier
coatings. Ceramics, in contrast to metals, are often more resistant to oxidation, corrosion and
wear, as well as being better thermal insulators. Except yttria stabilized zirconia, other
materials such as lanthanum zirconate and rare earth oxides are also promising materials
for thermal barrier coatings.

The above-discussed deficiencies and drawbacks of the prior art are overcome by the
method of the present inven tion wherein candidate ceramic materials are Systematically
Screened using the criteria of thermal conductivity, oxygen diffusivity, thermal expansion
coefficient, maximum tem perature capability, hardness, elastic modulus, density, and
chemical reactivity. Novel thermal barrier coatings discov ered in accordance with the
present invention comprise yttrium aluminum garnet (Y-AlsC), or YAG)-based ceram ics …