Design of a new yttrium silicate Environmental Barrier Coating (EBC) based on the relationship between microstructure, transport properties and protection efficiency
Language
en
Article de revue
This item was published in
Journal of the European Ceramic Society. 2022, vol. 42, n° 3, p. 1061-1076
Elsevier
English Abstract
Yttrium mono- and di-silicates are excellent candidate materials for Environmental Barrier Coatings (EBC), to protect Ceramic-Matrix Composites (CMC). A large distribution of microstructures can be generated by varying the ...Read more >
Yttrium mono- and di-silicates are excellent candidate materials for Environmental Barrier Coatings (EBC), to protect Ceramic-Matrix Composites (CMC). A large distribution of microstructures can be generated by varying the duration of sintering, the particle size distribution of the precursor and/or the deposition method. In the present work, investigations of the corrosion resistance of yttrium silicate coatings with various microstructures in the high temperature range, under different oxidizing environments are reported. An original experimental methodology has allowed quantifying the influence of the microstructure (especially grain size and grain boundary surface area) on properties such as ionic conductivity, resistance to oxygen diffusion, volatilization rate and surface recession, and showing that they directly affect their protection efficiency against oxidation. Based on these results, guidelines for the design of an optimized yttrium silicate EBC featuring microstructural and compositional variations are proposed.Read less <
English Keywords
Environmental barrier
Silicate
Conductivity
Recession
Microstructure
Diffusion coefficient
Origin
Hal imported