Hot Corrosion Behavior of Yttria-Stabilized Zirconia in the Presence of CMAS and CMAS + NaVO3 Mixture

The aim of this paper is to study the corrosion mechanism of CaO-MgO-Al2O3-SiO2 (CMAS) powder and CMAS + NaVO3 (hereafter referred to as CN) mixed powder on a yttria-stabilized zirconia (YSZ) block at different temperatures. In this paper, the CMAS and CN corrosion behavior of YSZ at 1200 °C and 1250 °C was studied. The results show that at 1200 °C, CMAS cannot completely melt, causing limited damage to YSZ. However, CN melts completely at this temperature, partially penetrating the YSZ interior and causing surface corrosion. At 1250 °C, both CMAS and CN melt completely. CMAS, characterized by high viscosity and shallow penetration, seriously damaged the YSZ surface layer. In contrast, CN, with its lower viscosity and enhanced penetration capability, induces internal corrosion of YSZ. Through the analysis of the corrosion mechanisms of CMAS and CN, it is concluded that CN poses a more significant threat to the integrity of thermal barrier coatings (TBCs).