Corrosion behavior of Yb4Hf3O12 ceramics exposed to Calcium-Ferrum-Alumina-Silicate (CFAS) coupled with water vapor at 1400 °C

In this work, the corrosion behavior of Yb4Hf3O12 ceramics under CFAS coupled with water vapor environment at 1400 °C for 2–50 h was investigated. Results show that the CFAS were rapidly dissolved into ceramics under test environment, and then the Yb-Ca-Si apatite and Hf-rich fluorite phases were re-precipitated. Simultaneously, the water vapor corrosion mainly induced grain surface corrosion, resulting in the formation of corrosion pits and ridge-like structures. Moreover, the pores and microcracks caused by water vapor corrosion offer additional penetration path for CFAS melt.