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 Yb 4 Hf 3 O 12 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. • The corrosion behavior of Yb 4 Hf 3 O 12 in a CFAS coupled with water vapor environment was investigated for the first time. • The reaction layer containing apatite and fluorite is an important factor for Yb 4 Hf 3 O 12 to resist CFAS corrosion. • Microholes caused by water vapor corrosion accelerate the CFAS infiltration. [ABSTRACT FROM AUTHOR]