摘要
Aero-engine is a key part of aircraft,the operating temperature of which is being pushed to unprecedented levels for higher engine efficiency and performance.To accomplish higher gas-inlet temperature of aero-engines,applying thermal barrier coatings(TBCs)on hot-section metallic components,or even replacing some of the metallic components in aero-engines with ceramic-matrix composites(CMCs)and applying environmental-barrier coatings(EBCs)on them,are effective methods and have been widely accepted.On the other hand,increasing aero-engines operating temperature causes the aircraft more easily be detected,thus stealth coatings are necessary for engines.Except the hottest part in aero-engines,other parts may not need TBCs or EBCs due to the relatively low operating temperature,but they still need protection from oxidation and corrosion.Hence,corrosion-resistant coatings are essential.In this paper,the latest progress of the above high-temperature protective coatings,i.e.,TBCs,EBCs,stealth coatings and corrosion-resistant coatings is reviewed,mainly including their materials,fabrication technologies and performance.In addition,due to the harsh operating environment,these protective coatings face many threats such as calcia-magnesia-aluminosilicates(CMAS)attack,causing premature failure of the coatings,which is also concerned in this paper.The work would provide a comprehensive understanding on the high-temperature protective coatings in aero-engines and guidance for developing advanced protective coatings for next-generation aero-engines.
