Porous Yb₂Si₂O₇ coating: A new‐type high‐temperature‐resistant abradable seal coating

Traditional abradable seal coatings (ASCs) face huge challenges for the requirements of next‐generation aero engines due to high inlet temperature (>1300°C) and non‐matched coefficients of thermal expansion for SiC based composites. Herein, a novel Yb 2 Si 2 O 7 seal coating was developed to meet the demands of high‐temperature resistance and match the coefficient of thermal expansion with SiC. The prepared Yb 2 Si 2 O 7 seal coating has excellent properties, including high porosity of 35.5%–23.3%, moderate hardness of 77.9–82.5 HR15Y, and high bond strength of 7.8–9.0 MPa. Adjusting spray current could effectively control the thickness, porosity, and hardness of the coating. More importantly, the coating also has good erosion resistance. Our results show that the fabricated porous Yb 2 Si 2 O 7 coating would have promising applications in the field of high‐temperature ASCs.