| About this Abstract |
| Meeting |
Materials Science & Technology 2019
|
| Symposium
|
Sandphobic Thermal/Environmental Barrier Coatings
|
| Presentation Title |
High Resolution Non-invasive Characterization of Calcium-magnesium-alumino-silicate Infiltration in Thermal Barrier Coatings |
| Author(s) |
Zachary Stein, Sandip Haldar, Chance Barrett, Johnathan Hernandez, Laurene Tetard, Ravisankar Naraparaju, Uwe Schulz, Seetha Raghavan |
| On-Site Speaker (Planned) |
Seetha Raghavan |
| Abstract Scope |
Calcium-magnesium-alumino-silicate (CMAS) deposits, which melt at turbine temperatures, rapidly penetrate thermal barrier coatings and solidify within the zirconia layer under temperature gradients. This work highlights non-invasive characterization offered by Photo-luminescence (PL)/Raman spectroscopy and Synchrotron X-ray diffraction measurements which provide the pathway for elucidating the degradation mechanisms due to CMAS ingression. The measurements are correlated with i) thermochemical attack mechanisms which reveal the extent of penetration of particulates into the TBC and ii) thermo-mechanical mechanisms which indicate the effects on strain compliance. The results demonstrate how we can assess the impact of CMAS on thermal barrier coatings by capturing the effects of the differences on strain and phase evolution with these high resolution techniques. The measurements pave the way for future ex-situ or in-situ studies that contribute towards a better understanding of failure mechanisms in a close-to-actual engine environment. |