Abstract
Alternative thermal barrier coating, functionally graded Al2O3/CYSZ was investigated for CMAS and hot corrosion melts attack under high temperature. Two different test setups were used to simulate the harsh environment of gas turbine engines. Thermal gradient and thermal cycling tests were carried out by using a static heat source laser. Commercial single-layer CYSZ was used as a comparison. As a result of XRD analysis and with the help of Rietveld refinement, the monoclinic transformation was compared for both TBCs. While there was no tetragonal-monoclinic transformation for a functionally graded coating because of protective inert alumina surface, CYSZ has %12.3 and %66.4 monoclinic transformation after thermal gradient and thermal cycle test at 1200 °C, respectively. The t-m transformation resulted in the failure of TBC because of the volume extension of zirconia and the TBC system. Microstructure, EDS and XRD analysis were performed to determine the failure of TBCs.
| Original language | English |
|---|---|
| Article number | 128688 |
| Journal | Surface and Coatings Technology |
| Volume | 444 |
| DOIs | |
| Publication status | Published - 25 Aug 2022 |
Bibliographical note
Publisher Copyright:© 2022 Elsevier B.V.
Funding
This work was supported by the Academic Staff Training Program (OYP) of the Council of Higher Education of Turkey. The authors thank Prof. Dr. Yılmaz Taptik and Hasan Huseyin Sezer for their contributions to the thermal spray and characterization process. The authors also thank Prof. Dermot Brabazon and Merve Nur Dogu at Dublin City University (DCU) for his support on SEM-EDS mapping analyses.
| Funders | Funder number |
|---|---|
| Council of Higher Education of Turkey |
Keywords
- ALO
- CMAS
- CYSZ
- Hot corrosion
- Thermal barrier coating
- Thermal tests