Adhesion strength and thermal shock properties of nanostructured 5La3TiYSZ, 8LaYSZ and 8CeYSZ coatings prepared by atmospheric plasma spraying

The effects of ceramic dopant species and amount on adhesive strength and thermal shock resistance behavior of nanostructured thermal barrier coatings (TBCs) were investigated in detail. Firstly, nanostructured 5 wt% La2O3+3 wt% TiO2+92 wt% YSZ(5La3TiYSZ), 8 wt% La2O3+92 wt% YSZ (8LaYSZ) and 8 wt% CeO2+92 wt% YSZ(8CeYSZ) coatings were prepared using atmospheric plasma spraying (APS) technology under the same technic parameters. Secondly, microstructure, adhesion strength and thermal shock behavior of three kinds of coatings were discussed. The results show that 5La3TiYSZ has the highest adhesion strength and the best thermal shock resistance in three kinds of coatings. The adhesion strength and thermal shock life for nanostructured TBCs heavily depend on ceramic materials. Among dopants nanostructured TiO2, La2O3 and CeO2 oxides, TiO2 can take relatively good effects in YSZ and the reason are also discussed using first principles.