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The efficiency of a gas turbine engine is highly dependent upon the clearance between blades and engine case. To control the over-tip leakage, an abradable coating system is sprayed on the case surface. In the high temperature section, a ZrO₂-8 wt% Y₂O₃ (YSZ) coating is usually applied as matrix. Pores in the coating are to enhance their abradability. In this study, poly-p-hydroxybenzoate (PHB) powder was used as a pore-forming material. To avoid burning loss of PHB during the spraying process, a sol-gel method was utilized to coat a TiO₂ shell on the PHB powder surface. The characteristics of the coatings were investigated in this work, such as morphology, porosity, hardness and abradability. The results show that the coated PHB improved the porosity of the YSZ coating, and then decreased the coating hardness. Finally, an abradability test was utilized to exhibit the incursion depth increased with the increase of coating porosity.