CMAS corrosion resistant of La3+-Yb3+-Ce4+ co-doped ZrO2 based TBCs: Experimental and theoretical research

The CaO–MgO–Al 2 O 3 –SiO 2 (CMAS) corrosion resistance of La 3+ -Yb 3+ -Ce 4+ co-doped ZrO 2 (LYZC) ceramic was systematically discussed via experiment and first-principles calculation. Results demonstrate that at the CMAS/RE-ZrO 2 interface, RE is dissolved in molten CMAS to form some RE-apatite particles, which effectively inhibits CMAS penetration. Compared with La 3+ doped ZrO 2 (LZ), LYZC owns a better ability to maintain the coating microstructure under CMAS corroded, which is conducive to alleviating CMAS penetration. This conclusion is also confirmed by the low diffusion coefficients ( D ) of RE and Zr in CMAS/LYZC(111), which are only 2.305–5.556 × 10 −8  m/s and 2.694–3.421 × 10 −8  m/s, respectively. Furthermore, the small electrostatic potential difference (Δ V  = 1.578–1.654 eV) of the CMAS/LYZC(111) terminal layer suggests that molten CMAS does not easily adhere to the LYZC surface.