Excellent abradability of a novel seal coating with spherical closed-pore for next-generation aero-engine application

Abstract To improve the aero-engine compressor efficiency and reliability, abradable seal coatings need to have good abradability resulting from reduced hardness. However, low hardness is often coupled with low bonding strength, resulting in coating spalling off failure during service. To defeat the conflicts between low hardness and high bonding strength, a new abradable seal coating with a spherical closed-pore structure was prepared in this study. Compared to conventional coatings, the new coating has lower hardness and higher bonding strength. In the high-speed scraping test, the coating presented excellent abradability without any coating spalling. The new abradable seal coating is promising to improve the efficiency and reliability of the next-generation aero-engine.