Preparation and characterization of nanostructured La₂Zr₂O₇ feedstock used for plasma spraying

The nanostructured La₂Zr₂O₇ (LZ) feedstock with high density, suitable size distribution and nearly spherical morphology which can be used for plasma spraying was prepared by spray drying in this study. The spray drying process was discussed. In addition, the formation mechanism of feedstock with hollow shell structure was discussed by finite element method in this paper. The double ceramic layer (DCL) LZ/YSZ (yttria stabilized zirconia) thermal barrier coatings were prepared using the as prepared LZ feedstock. The average grain size computed by Scherrer formulation, the observation of powder size by Transmission Electron Microscope (TEM) and “single splat” deposition experiment indicate that the as prepared LZ feedstock is nanostructured feedstock.