화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.102, No.4, 2029-2040, 2019
CaO-MgO-Al2O3-SiO2 corrosion behavior of air-plasma-sprayed (LaxYb1-x)(2)Zr2O7
The CaO-MgO-Al2O3-SiO2 (CMAS) corrosion of thermal barrier coatings (TBCs) is a crucial problem for the lifetime of blades and vanes of jet engine and gas turbine at high operating temperature. Although many new alternative materials for TBCs have been developed in recent years, their application is limited by the CMAS corrosion. On the other hand, the composition difference of CMAS between regions makes solving this problem very difficult. Therefore, in this study, the yearly composition changes of sand-dust around Beijing area were investigated. The high-temperature corrosion behavior of air-plasma-sprayed 8YSZ and newly developed (LaxYb1-x)(2)Zr2O7 TBCs by the representative sand-dust of Beijing was investigated. In comparison, a universally used CaO-riched composition of simulated silicate deposit was also adopted for the TBCs corrosion test. It is found that the (LaxYb1-x)(2)Zr2O7 TBCs performs much better anti-corrosion behavior than that of 8YSZ, both by Beijing sand-dust and simulated one. Particularly, Yb2Zr2O7 TBCs appear to be the optimum material against silicate deposits attack. The mechanism of silicate deposits corrosion has also been discussed.