Thick plasma sprayed thermal barrier coatings are suitable for thermal and hot corrosion protection of metal components in land-based turbine and diesel engines. In this work, ceria-yttria co-stabilized zirconia coatings were deposited by atmospheric plasma spraying in a mixture of non-transformable tetragonal t′ and cubic c zirconia phases. Free-standing coatings were isothermally annealed at 1315 °C for different times and their crystal structure was studied by XRD. No phase decomposition occurred. Columnar grains grew in the molten splats with increasing annealing time according to a preferential direction and, after 50 h of heat treatment, they were partially replaced by equiaxed grains. Both in-plane and out-of-plane thermal expansion coefficients (CTEs) were measured from coating expansion during heating. The CTE was slightly sensitive to thermal exposure in out-of-plane direction, whereas it kept almost constant in plane direction. The specific heat capacity Cp of annealed coatings, measured by differential scanning calorimetry (DSC), decreased in comparison with as-sprayed coating, due to high-temperature sintering. © 2009 Elsevier Ltd and Techna Group S.r.l.
All Science Journal Classification (ASJC) codes
- Process Chemistry and Technology
- Ceramics and Composites
- Electronic, Optical and Magnetic Materials
- Materials Chemistry
- Surfaces, Coatings and Films
Di Girolamo, G., Blasi, C., Schioppa, M., & Tapfer, L. (2010). Structure and thermal properties of heat treated plasma sprayed ceria-yttria co-stabilized zirconia coatings. Ceramics International, 36(3), 961 - 968. https://doi.org/10.1016/j.ceramint.2009.10.020