TY - JOUR A1 - Mack, D. E. A1 - Laquai, René A1 - Müller, Bernd R. A1 - Helle, O. A1 - Sebold, D. A1 - Vaßen, R. A1 - Bruno, Giovanni T1 - Evolution of porosity, crack density, and CMAS penetration in thermal barrier coatings subjected to burner rig testing T2 - Journal of the American Ceramic Society N2 - Degradation of thermal barrier coatings (TBCs) in gas‐turbine engines due to calcium–magnesium–aluminosilicate (CMAS) glassy deposits from various sources has been a persistent issue since many years. In this study, state of the art electron microscopy was correlated with X‐ray refraction techniques to elucidate the intrusion of CMAS into the porous structure of atmospheric plasma sprayed (APS) TBCs and the formation and growth of cracks under thermal cycling in a burner rig. Results indicate that the sparse nature of the infiltration as well as kinetics in the burner rig are majorly influenced by the wetting behavior of the CMAS. Despite the obvious attack of CMAS on grain boundaries, the interaction of yttria‐stabilized zirconia (YSZ) with intruded CMAS has no immediate impact on structure and density of internal surfaces. At a later stage the formation of horizontal cracks is observed in a wider zone of the TBC layer. PB - Wiley CY - Oxford KW - Characterization KW - CMAS KW - Synchrotron X‐ray refraction radiography KW - Thermal barrier coatings PY - 2019 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/47804 AN - OPUS4-47804 SN - 0002-7820 SN - 1551-2916 VL - 102 IS - 10 SP - 6163 EP - 6175 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany