Application of Thermal Barrier Coating on Foreign Aero-engines

       Thermal barrier coating can significantly reduce substrate temperature, high hardness, good chemical stability, and has the advantages of preventing high temperature corrosion, prolonging the service life of hot end components, improving engine power and reducing fuel consumption. The emergence of TBCs has greatly improved the performance of aircraft engines. Performance opens up new avenues. Since the 1970s, developed industrialized countries such as the United States, Britain, France, and Japan have all competed to develop TBCs coatings, which have been widely used in the hot end of aero-engines such as blades, combustion chambers, heat shields, nozzles, flame tubes, and tailpipes. on the part.



In 1976, the MgO partially stabilized ZrO2 thermal barrier coating developed at the Lewis Research Center of NASA in the United States was first verified on the J75 engine, and then successfully used in the combustion chamber of the engine, which was later called the first-generation aerospace thermal barrier coating. Floor. In the early 1980s, P&W successfully developed the second generation plasma sprayed thermal barrier coating - PWA264. Its ceramic surface layer is atmospheric plasma sprayed yttria partially stabilized zirconia (YSZ) with a mass fraction of 7%, and the metal bonding layer is more oxidation-resistant low pressure plasma sprayed (LPPS) NiCoCrAIY. After the successful application of the PWA264 coating on the turbine blades of the JT9D engine, it has been experimentally verified and applied on the turbine blades of the PW2000, PW4000 and V2500 engines. As of 1992, the coating was used on the turbine blades of JT9D, PW2000, PW4000 and V2500 engines, which had accumulated more than 4 million flight hours. In the late 1980s, in order to meet the higher temperature requirements, P&W successfully developed the third-generation turbine blade EB-PVD thermal barrier coating-PWA266. The coating adopts EB-PVD to prepare 7YSZ ceramic surface layer, low pressure plasma spraying (LPPS) NiCoCrAIY metal bonding layer, the coating eliminates blade creep fatigue, fracture and spalling of anti-oxidative ceramics on blade surface, making its life 3 times longer life than blades without the coating. With its excellent durability, thermal spalling resistance and heat resistance, PWA266 was successfully tested on JT9D and PW2000 engines, and was first applied to PW2000 engine turbine blades in 1989, and then to JT9D -7R4, V2500 , F100 - PW -229 and F119 and other engine turbine blades. After the coating is applied, the working temperature of the high-pressure turbine blades of the F119 engine can be increased by about 150K compared with the blades without the coating. In addition, PW has used thermal barrier coatings on the fan blades, compressor blades, combustion chambers, turbine blades, etc. of the JT3D and JT38D engines.



At the same time, American GEAE Company successfully developed APS and EB-PVD thermal barrier coatings in the late 1980s and early 1990s, and used MCrAIY prepared from LPPS on the second-stage turbine guide vanes of the CF6-50 engine. Thermal barrier coating of bonding layer and APS ceramic layer; thermal barrier coating of PtAI bonding layer and EB-PVD ceramic layer on the 1st stage rotor blades of the CF6-80 engine, and the 2nd stage turbine guide vane adopts Thermal barrier coating of MCrAIY bonding layer and APS ceramic layer prepared by APS; thermal barrier coating of aluminum bonding layer and EB-PVD ceramic layer was used on the first-stage turbine guide vane of CFM56-7 engine; On the F414 engine, a thermal barrier coating of EB-PVD ceramic layer is used.



In addition, the British Rolls-Royce Company has gradually applied a large number of TBCs to military and civilian engines. More than 200 parts of the Spey engine use thermal barrier coatings, especially on the 1st to 3rd stage turbine blade crowns, which improve blade reliability and improve engine efficiency. In order to improve the reliability of the combustion chamber of the engine and prevent thermal deformation and then cracks, Rolls-Royce also uses APS zirconia coating on the surface of the combustion chamber liner of the RB211 engine, which greatly improves the service life of the combustion chamber. EJ200 engine high-pressure turbine working blades use double-layer plasma-deposited thermal barrier coating (surface layer is YSZ, bonding layer is NiCoCrAIY), which prolongs blade life and improves temperature resistance.



French SNECMA company has also applied EB-PVD thermal barrier coating to M88-2 engine AMI single-crystal alloy turbine blades, which reduces the cooling air flow of the turbine, prolongs the service life and improves the efficiency.



According to reports, TBCs are currently used in almost all military and commercial aircraft engines in the United States, and about 300t of zirconia materials are used in TBCs each year. In the next 10 years, TBCs will reach an annual growth rate of 12%, of which in engine components The annual growth rate will reach 25%, and the application development prospect is very broad.