Examination of the Characteristics of Residual Pores in High Temperature Sintered Plasma-Sprayed La₂Zr₂O₇ Coatings

In this study, La₂Zr₂O₇ coatings produced by atmospheric plasma spraying were heated to 1300°C for up to 100 h. Residual pores in the coatings were characterized by SEM. Porosity was found to decrease with increasing sintering duration, although large pores still existed after 100 h. The relationship between the opening of residual pores and sintering time was closely analyzed and is described in detail. The results presented in the paper can inform the design of pores that endow TBCs with higher sintering resistance.