Stabilization of a novel mixed solution precursor used for preparing YSZ abradable sealing coatings

The mixed solution precursor was prepared by adding the yttria stabilized zirconia (YSZ) nano-particles into the YSZ solution precursor to obtain the ceramic-based abradable sealing nanostructure coatings with the plasma spraying . The stability of the solution precursor must have the fluidity and take precautions to prevent the nano-particles sedimentation too quickly in the tube, resulting in clogging during the spraying process. The measurement of Zeta potential and rheology with varying dispersant were used to research the stabilization and the viscosity of the mixed solution precursor. The microstructure changed, and the phase composition of the mixed solution precursor coatings were evaluated via scanning electronic microscopy (SEM) and X-ray diffractograms (XRD). The result showed that the Zeta potential value and the liquidity of mixed solution precursor improved after using Poly (acrylic acid) (PAA) as a dispersant. The viscosity significant changed as the PAA content, the nano-particles, and the concentration of the precursor solution increased. The suspension plasma spraying (SPS) and solution precursor plasma spraying (SPPS) were combined to obtain a more complex structure in the coating microstructure of the mixed solution precursor with macropores and micropores. This contributed to further improve the structure diversity of coatings. More importantly, the mixed solution precursor coating has the lowest friction coefficient is 0.3 and exhibited the characteristic of excellent tribological performance .