Development and Application of Thermal Barrier Coatings in China

       my country started late in the research of thermal barrier coatings, and thermal barrier coatings are classified as secret technologies in industrialized countries, and my country has been blocked. Therefore, my country's thermal barrier coatings are still significantly higher than foreign advanced technologies. difference. In the 1960s and 1970s, plasma spraying was used to prepare thermal barrier coatings for combustion chamber flames, etc., and then gradually began to be applied to other parts of aero-engines. In order to meet the needs of the development of aero-engines in my country, in the mid-1990s, relevant units carried out research on the preparation of thermal barrier coatings by electron beam physical vapor deposition technology, and imported high-power multi-electron beam physical vapor deposition equipment from abroad. With the development of aerospace technology, my country's thermal barrier coating technology has also made great progress. Several key technologies for the preparation of thermal barrier coatings for turbine blades, such as bonding layer composition and structure control technology, ceramic layer columnar crystal growth orientation control technology, blade coating thickness control technology, and post-coating gas film cooling hole size control technology, are developed. YSZ/MCrAIY double-layer thermal barrier coatings have been applied to hot end components such as blades and combustor nozzles of many types of gas turbine engines. At the beginning of the 21st century, the thermal barrier coating was successfully prepared on the first-stage turbine blade of a certain engine by electron beam physical vapor deposition technology.



At present, the application research of thermal barrier coating on aero-engine turbine blades in my country has been started and received attention. Thermal barrier coatings have been sprayed on some turbine blades, and staged results have been achieved. The application of thermal barrier coating technology can greatly improve the comprehensive performance of engines and ground gas turbines and prolong their service life. It is one of the key technologies in the development of high-performance engines and gas turbines. With continuous progress, the demand for thermal barrier coatings will become more and more huge, and thermal barrier coatings will have a wide range of application prospects in hot-end components in aerospace, ships, nuclear industry, automobiles and other fields.



At the same time, the thermal barrier coating manufacturing process and equipment will be continuously improved, the designers will have a more comprehensive understanding of the thermal barrier coating, and the thermal barrier coating technology will be more familiar. layer will gain huge development in our country.



The research on thermal barrier coatings in China started late, and the research on plasma sprayed thermal barrier coatings started in the 1970s. In the late 1980s, AVIC Beijing Institute of Aeronautical Materials, Beijing University of Aeronautics and Astronautics, AVIC Beijing Institute of Aeronautical Manufacturing Engineering and other units successively carried out research on the preparation of thermal barrier coatings by EB-PVD. During the "Eleventh Five-Year Plan" period, the Beijing Institute of Aeronautical Materials used the EB-PVD method to prepare YSZ double-layer structure TBCs, breaking through the key material and technical problems of the double-layer structure thermal barrier coating system, and all the performance indicators of TBCs reached the expected assessment objectives. Through the introduction of a multifunctional improved physical vapor deposition device from abroad, the device not only strengthened the research and production strength of Beijing Institute of Aeronautical Materials in the field of TBCs, but also promoted the development of this industry in China. The successful application of EB-PVD technology in domestic aero-engine turbine blades has been achieved, meeting the major needs of my country's aero-engine development.



In addition, according to the application of thermal barrier coating technology in my country's industry, it can be briefly summarized as follows:



(1) New aero-engine blades require thermal barrier coatings. During the "Ninth Five-Year Plan" period, the aviation industry has developed pre-research work for multiple models. In the early stage, the research and development of key components of high thrust-to-weight ratio engines has been started. The components have been deeply developed, and small-scale applications of TBCs have been realized on a certain type of engine turbine blade.



(2) Thermal barrier coatings are used in naval gas turbines. In the manufacturing process of a certain type of marine gas turbine imported from Ukraine, which was contracted by Xi'an Aero Engine (Group) Company, the first-stage guide vanes of the turbine adopt the plasma thermal spraying process and the working blades adopt the EB-PVD process, both of which require the application of thermal barriers. coating.



(3) At present, a new type of engine flame tube, combustion chamber components, and casing parts also use thermal barrier coatings. In addition, in the field of domestic aero-engine technology, the process of preparing thermal barrier coatings by plasma spraying has been successfully applied on the turbine guide vanes and heat shields of a new type of aero-engine.



(4) For the active engine, this process is also used in the repair process, and the thermal barrier coating is used to repair the hot end parts of the engine, which prolongs the refurbishment life of a certain type of engine.



The research and application of ceramic thermal barrier coating has a history of nearly 40 years, but its application scope is mainly concentrated in the aerospace field. With the continuous efforts of scientific and technological personnel, the application range of ceramic thermal barrier coatings is constantly expanding. At present, ceramic thermal barrier coatings are not only used in defense fields such as aviation, aerospace, ground gas turbines, ship energy, nuclear industry, etc., but also successfully used in power equipment, machinery manufacturing steel, metallurgy, petrochemical, textile, printing, Electronics, electric power and other industries.