CMAS Corrosion Resistance Behavior and Mechanism of Hf6Ta2O17 Ceramic as Potential Material for Thermal Barrier Coatings
Sai Liu, Qing Liu, Xiaopeng Hu, Jinwei Guo, Wang Zhu, Fan Zhang, Jie Xia
Abstract
Thermal barrier coatings (TBCs) have been seriously threatened by calcium-magnesium-alumina-silicate (CMAS) corrosion. The search for novel ceramic coatings for TBCs with excellent resistance to CMAS corrosion is ongoing. Herein, CMAS corrosion resistance behavior and the mechanism of a promising Hf6Ta2O17 ceramic coating for TBCs are investigated. The results show that temperature is the most important factor affecting the CMAS behavior and mechanism. At 1250 °C, the corrosion products are composed of dense reaction products (HfSiO4, CaXHf6−xTa2O17−x) and CMAS self-crystallization products. At 1300 and 1400 °C, the corrosion products are mainly dense CaTa2O6 and HfO2, which prevent further CMAS infiltration.