High-push: China began the pre-research of high-performance propulsion system engineering in 1980, referred to as high-push pre-research. The network is often called push.
High-push target: provide technical reserve with F404 engine as the target. Taking 624 as the general division of labor, 24 factories, research institutes and universities across the country participated. 1989- 1992, the full-scale test pieces of three high-voltage components were designed and tested, and the core machine was designed and tested on 91-1.
Core pusher:1June 65438, 994+1October, the core pusher reached the design index.
Middle push refers to the middle push core machine, that is, the middle push weight ratio core machine. High push projects include middle push core machines, but they can also include high push-to-weight ratio core machines.
The achievements of pushing the core machine:
1. Based on the three-dimensional flow theory, Professor Wu Zhonghua established the design system of quasi-three-dimensional axial compressor under inviscid conditions. A high-load transonic turbine aerodynamic design system is established. Master the overall, pneumatic, cooling, structure and strength design technology of advanced core machine and the matching technology between the three components.
2. A seven-stage high-pressure compressor with pressure ratio of 7.02, efficiency of 0.839 and surge margin of 24.7%.
3. Study on the short-ring combustion chamber with evaporation tube. The flame tube length of short-ring combustion chamber with pneumatic atomizing nozzle is 190 mm, the average outlet temperature is 1662K (temperature rise of 850℃), the temperature field is uniform, and the wall temperature is less than 900℃.
4. The full-scale turbine components with air conditioning have stood the test of the core engine 1600 ~ 1650k and 16500rpm.
5. "Convection-Impact-Film" composite air-cooled blade test and a set of advanced design methods and computer programs. The average cooling level of guide vanes is 36 1 ~ 438℃, while that of moving vanes is 320 ~ 357℃, and the comprehensive cooling effect of the coating is 487℃. The gas temperature in front of the turbine can reach 1600 ~ 1650 K by using composite cooling technology and coating heat insulation technology.
6. Climb the steps with a push-to-weight ratio of 8.
Development of core engines with high thrust-to-weight ratio in the past 95 years;
1.84 started the demonstration of thrust-to-weight ratio 10 engine pre-research technology, 1988 held a seminar on pre-research topics in April, and 1990 formally established the project.
2. 1994 completed the top-level design of six overall plans, completed the project guide and comprehensive demonstration, 1993-96 carried out cooperation with Russia.
3. The overall scheme of the engine with thrust-to-weight ratio 10 has been basically determined. Some topics, such as the research of three-stage compressor with average stage pressure ratio of 1.62, have made good progress.
This paper points out the development of foreign engines with thrust-to-weight ratio 10, that is, the goal of high thrust-to-weight ratio core engines. It requires high thrust-to-weight ratio, low fuel consumption, high reliability and thrust vector. The cycle parameters of the thrust-to-weight ratio 10 engine of the US Air Force are: bypass ratio 0.2 ~ 0.3, total pressure increase ratio 23 ~ 27, throttle ratio1.10 ~15, and pre-turbine temperature/kloc-0. Typical foreign representatives are F 1 19, EJ200, M88 and P2000. Russia's P2000 has come to a standstill due to economic difficulties. Liu Daxiang thinks that this index is close to F 1 19 and EJ200, and the concept research of 10 ~ 20 and a few key technologies should be properly arranged.
China's engine development is similar to that of the United States, and the research on application basis and exploration and development belongs to pre-research. The pre-research stage in the United States also belongs to pre-research, which is divided into technical verification machine and model verification machine. China uses the concept of "advanced technology demonstration and verification". In the future, the two stages of engineering development and use development are the same as those in the United States. Liu Daxiang put forward the development path of "applied research-advanced components-core machine-verification machine".
1995, the core engine has not yet entered the stage of "advanced technology demonstration and verification". Liu Daxiang thinks that this is an advanced technical demonstration and verification for developing 7500 ~ 10000 Dan turbofan engine when necessary, which is more advantageous than the pre-research of 10 thrust-to-weight ratio to complete this process.
This article left such a mystery:
The divergence between 1. push-to-weight ratio 8 and 10 core machine development verification machine.
2. The thrust-to-weight ratio is 10. Independent research and development of core engines and differences in cooperation with Russia.
3.XXX engine and XXX engine are two engineering models.
4. The engine pre-research with thrust-to-weight ratio 10 can absorb the development experience of ××××××× engine on the basis of thrust-to-weight ratio 8, core machine and technical verification machine.
In the 5th issue of Aviation Knowledge in 2000, the article "The Heart of Aviation Power-A Record of Liu Daxiang, an Aviation Power Expert" was published. Liu Daxiang successively served as the project chief designer and the first chief designer for the pre-research of high-performance propulsion system and the development of advanced core machine engineering in the Seventh Five-Year Plan and the Eighth Five-Year Plan. The "advanced core machine project" mentioned in this paper refers to the middle push core machine, and 1994 was tested twice at the beginning of this year.
Beihang University further disclosed this point in the article "Road Choice of Aeroengine Development in China".
According to the analysis of Advanced Research Laboratory and Beihang University 1.89, the gap between the available performance level and the United States is about 20 years, and by 2000, the gap is about 25 years. There is also a document saying that by 2005, we will be about 20 years behind the developed countries.
2. In the mid-1980s, the turbofan 10 engine developed on the basis of a foreign core engine is expected to be equipped with troops in 2005, with a thrust-to-weight ratio of 7.5, which is equivalent to the technical level of foreign third-generation engines, and the gap has been shortened to about 20 years.
3. The technical key to break through the thrust-to-weight ratio 10 engine is the practical need. Foreign experience is that it only takes 3-5 years to develop a new machine on a mature core machine, and the capital is only about 40% of the new machine.
4. China's international cooperation is mainly cooperative production, which has not reached the stage of cooperative research and development.
5. The article holds that it is necessary to "increase investment and unswervingly develop the core machine of the corresponding level according to the national conditions".
Academician Liu Daxiang recently disclosed the development of WS 13 engine of Liyang Company. The article explains:
1 prototype. WS 13+03 is the main fighter power in active service.
It can be modified and developed into WS 13 based on the core machine.
Author: sparrow
Special statement: Super Base Camp prohibits the use of this article in any way.
Superalloys are the general name of iron-based, nickel-based and cobalt-based superalloys, also known as superalloys. Iron-based alloys are generally used at a lower temperature than nickel-based alloys, and can be used as parts at moderate temperatures, such as turbine disks used below 700℃. Nickel-based alloys are used to manufacture hot-end components that bear severe stress, such as turbine blades, guide blades, combustion chambers, etc. In advanced engines, nickel-based alloys account for half of the total weight. Cobalt-based alloys are widely used as guide vanes because of their good thermal corrosion resistance and thermal fatigue resistance.
With the development of directional solidification, single crystal and ultra-pure melting technology, foreign casting alloys have developed from directional solidification to single crystal. Single crystal alloys have also developed three generations of products. Single crystal alloy is necessary to improve the pre-turbine temperature and high thrust ratio. The second and third generation single crystal alloys are mainly used as engine blade materials abroad. At present, the third generation single crystal alloy with low cost (less Re) and porous single crystal diffuser blades have been developed. The fourth generation single crystal was developed.
The first generation powder alloys used for turbine disks of high thrust-to-weight ratio engines include In 100, Rene95, APK- 1, зпнп alloys, etc. GE adopts HIP, HIP+ hot die forging, HIP+HIF (isothermal forging) and EX (extrusion) +HIF powder disks and shafts. The amount of эпэп74 1hпп alloy developed in Russia is the largest, which is above 1550MPa, and the permanent stress at 750℃ and 100h reaches 750Mpa. The main manufacturing process of эпп 962 п high strength alloy is 700℃, which is similar to Rene95. Adopting master alloy melting and electrode rod casting processing → plasma rotating electrode milling → powder treatment → powder sleeve sealing welding → hot isostatic pressing forming → heat treatment → machining → inspection → finished product.
The second generation powder alloys used for engine turbine disk with thrust-to-weight ratio of 10 include Rene88DT, N 18, MERL-76 and з 10875 alloys. The transformation from high-strength alloy to damage-resistant alloy was realized, and the strength decreased slightly, but the fatigue crack growth rate decreased greatly, and the technological properties were improved. The design service temperature reaches 750℃ or higher. Divergent cooling channels are made by casting and laser drilling.
In the third generation, two-component (AF 1 15+MER-76) and double heat treatment combined disks were developed. Mechanical alloying alloy adopts Y2O3 (
Technology is of great significance to the development of single crystal alloys, and the Eight Immortals have their own magical powers when crossing the sea. At present and in the future, the melting methods of superalloys are:
Single melting: AAM (electric arc furnace melting), AIM (induction furnace melting), VIM (vacuum induction furnace melting), vacuum arc melting (VAR), electroslag melting (ESR), electron beam melting (EBM), electron beam cold chamber furnace melting (EBCHR), plasma electric arc furnace melting (PAF) and plasma induction furnace melting (PIF).
Double melting: VAR (vacuum arc remelting), VADER (vacuum arc double electrode remelting), VIR (double vacuum remelting), EVR (vacuum induction slag remelting), NER (non-consumable), PAR (plasma remelting), EBM (electron beam remelting), VEB or VIM+EBCFM (vacuum induction plus electron beam), NEB (non-consumable).
Tertiary smelting: VIM+VAR+ESR, VIM+ESR+VAR, NAV+EBM+VAR.
Argon atomization is widely used in Europe and America. The cooling rate of powder is high, and the grain is very fine (-3 microns), but the purity of powder is slightly poor, so the hot isostatic pressing method is mainly used, and now it is developing in the direction of no ceramic fine powder. Atomization by plasma rotating electrode is widely used in Russia. Hot isostatic pressing (HIP) and hot extrusion are the key technologies of powder forming, which can directly form a disk, or make a preform first and then forge it into a disk at isothermal temperature. Direct hot isostatic pressing (HIP) is much cheaper, but it requires good powder quality, so it is only used in Russia at present. Use hot isostatic pressing, thermo-mechanical treatment, heat treatment, etc. A dual-performance disk with high core strength, good high and low cycle fatigue performance and good persistent creep performance at the edge of the disk was developed, which expanded the service temperature range of the disk. Dual-performance disc has been applied to engines such as F 1 19. The hot isostatic pressing integral parts of blades and powder disks have also been put into use, which greatly improves the turbine speed.
There are "five more and five less" in the aviation materials industry in China: imitation is more and innovation is less, low water is more and high water is less, research and development is more and improvement is less, rewards are more and practicality is less, and one material is more and more. Super alloys is also called heat-resistant alloy, heat-resistant alloy or super alloys. Domestic code: GH prefix refers to deformed superalloy (FGH refers to powder melting), cast superalloy K, directionally solidified alloy DZ, single crystal alloy DD and intermetallic compound alloy ic. In addition, among titanium alloys, TA stands for α titanium alloy and TB series stands for? T-type titanium alloy, TC series represents α+? T-titanium alloy.
The first generation of 650℃ high-temperature alloy powder smelting FGH95 in China was developed in 1977, and some research equipment was imported from Heraeus company to imitate Rene95 alloy. At the end of 1984, a full-size turbine disk with a diameter of 420mm was forged, which basically reached the performance of Rene95. The master alloy smelting, argon atomization powder making, powder treatment, hot isostatic pressing forming, isothermal forging, heat treatment, ultrasonic flaw detection and surface strengthening were studied, and it was found that the technological problems in industrial production were serious. Industrialized plasma rotating electrode milling equipment and disc production line were imported from Russia, and all of them were put into operation at the end of 1995, which fundamentally solved the powder quality problem of superalloy milling. 1995, southwest aluminum processing plant successfully forged a φ630mm 10A powder metallurgy FGH95 alloy turbine disk by ladle forging process. After painstaking research, it passed the quenching pass and obtained a turbine disk that cooled rapidly without cracking. However, if problems are found, the process route of HIP+ isothermal forging (or hot die forging) will be adopted in the future. The service temperature of FGH95 alloy is 650℃, and the tensile strength can reach 1500Mpa. Under the stress conditions of 650℃ and 1035MPa, the durability life is more than 50 hours.
At present, Inconel 7 18 and Hastoloyx powder superalloys account for 60% of advanced engine superalloys abroad. Fushun Iron and Steel Works, Shanghai No.5 Iron and Steel Works and Great Wall Iron and Steel Works produce GH4 169 (imitation IN7 18). In addition, China is currently focusing on the construction of GH4 169 production technology and product serialization. GH4 169 High-performance hard-to-deform disc superalloy with working temperature below 760℃. Melting methods and levels of IN7 18 alloy at home and abroad;
VIR abroad, American CM company O, N, S= 1ppm.
Calcium oxide crucible
EBCHR O、S=4~5ppm N=20~40ppm
EBR data is unknown.
VIM+ESR+VAR data is unknown.
VIM+EBR O=7ppm N=60ppm
Domestic VIM+ electromagnetic stirring s
VIM+VAR or VIM+ESR data is unknown.
The melting data of cold-wall crucible is unknown.
VIM(CaO crucible) o, N=20ppm S=5ppm.
The forging control models of IN7 18 and Waspaloy were determined by Zhong Zengyong of the Iron and Steel Research Institute around 2000 to control the forging process. In 2000, Guizhou Anda Aviation Forging Co., Ltd. developed the first GH4 169 low-pressure turbine shaft in China by integral forging process. According to the website of Xinyi Machinery Factory, the blade of the high-pressure compressor of China Core Pusher is made of GH4 169 alloy, and the blade has an arc-shaped rod tooth structure in the circumferential direction. In the data of die forging technology transfer in China, GH4 169 materials and turbine disk production technology have been used in industrial trial production of key components of model engines, installed and debugged, and entered the application research. At the same time, 28 kinds of high-temperature alloy die forgings were successfully developed by using the "composite cladding die forging" technology, which were used for urgently needed high-temperature alloy turbine disks such as GH698, GH 169 and GH 132 (note: GH4 169 belongs to the alloy series of GH 169). GH4 169 carried out the background research of high performance aero-engine turbine disk and compressor disk.
DD3 and FGH95 powder disks manufactured by Institute of Aeronautical Materials provide key materials for advanced turboshaft engines (both of which are first applied in China). NiCoCrAlTaY six-element alloy powder of Guangzhou Institute of Nonferrous Metals was used for DD3 high-temperature anti-corrosion coating, which solved the urgent need. The first generation of low-density and low-cost single crystal alloy DD3 can reach the high temperature of 1020℃. Now it has been extended to many types of aircraft and become the first generation of single crystal alloy really used in aviation in China.
At present, China is developing high-temperature alloy forgings, disks and rings, and carrying out research on the second and third generation turbine disk powder superalloys and advanced powder superalloys for dual-performance composite powder disks. Study GH586, GH742W and other processes to reduce the cost of high-performance disks and expand their applications. Develop a new generation of low-cost turbine blade single crystal superalloy. At present, IN909 and IN783 for high thrust-to-weight ratio engine casing, oxide dispersion strengthening alloy for high temperature ablation of combustion chamber and Ni3Al-based intermetallic compound for ablation resistant parts have been determined. FGH96 and FGH97 developed by Iron and Steel Research Institute can be used at 750℃. The application research of the second generation FGH96 powder turbine disk material was carried out by Beijing Institute of Aeronautical Materials, and the prealloyed powder was prepared by plasma rotating electrode method.
1 of WP 13AII compressor,1Cr1kloc-0/niw2mo stainless steel forgings for the second-stage rotor blades and disks, compressor shaft and eighth-stage stator blades, and all other rotor blades, disks and stator blades are TC1/kloc-. The flame tube is made of GH3044, and its surface is coated with W-2 high temperature ceramics. Installation edge GH 10 15. The material of stabilizer and heat shield is GH3 128, and the cylinder is GH99. The guide vanes of HP and LP turbines are made of K403. 1 rotor blade material K4 17. The second-stage rotor blade materials GH4049 and WP 13FI are DZ4 directionally crystallized heat-resistant alloys.
Guizhou Xinyi Machinery Factory cooperated with Beijing Institute of Aeronautical Materials in directional solidification technology of DZ4 alloy, completed the technical transformation of 524 1 directional crystallization furnace in the United States, and established the largest directional solidification production line in China. After the use of WP 13FI, the engineering application research of the new material IC6 alloy directional solidification secondary guide vane in the "863" plan was carried out, and it was passed by the office at the end of 1996. IC6 replaces import and is actually used together with WP 13B of J8IIM. The initial melting temperature of IC6 blade is1310-1320℃, and the service temperature exceeds 1 100℃, and the durability level reaches the highest level in the world. The secondary guide vanes of IC6 and IC6A (plus Y)WP- 13F engines (life extension of 500 hours) were trial-produced, and the hanging test was carried out. The first-stage guide vane of 10A engine was trial-produced with IC6, and the ground hanging plate test was carried out to replace cobalt-based alloy, which further improved the alloy performance and technology and better met the engineering application requirements. The application and development project of Ni-Al intermetallic compound has improved the qualified rate of WP-65438+3B secondary guide vane billet to 50-60%, reaching the level of mass production of parts. "Developing the first and second stage low-pressure turbine blades of FWS 10 engine by directional solidification technology without allowance" won the third prize of 1999 (website of Nanchang Institute of Aeronautical Technology).
WP 13B blades have been put into production:
1. First-class DZ4 alloy with three cooling holes, serrated crown, directional solidification, precision casting turbine blade.
2. Two-stage DZ4 alloy serrated crown directional solidification precision casting turbine blades.
3. First-class DZ4 alloy hollow integral directional solidification guide vane.
4. The second-order IC6 intermetallic compound Ni3Al-based superalloy is used for directional solidification of guide vanes.
It should be pointed out that the application of DD3 and FGH95 powder discs in 10A engine has not been reported successfully. WP 13F 1 DZ4 was first used for the second stage rotor blade of steam turbine, and then it was extended to WP 13B. WP 13B uses IC6 as the second-stage rotor blade for the first time, and GH4 169 is used for the middle thrust core engine for the first time. DD3 is a single crystal alloy, FGH95 is a deformed superalloy, DZ4 is a directionally solidified alloy, and GH4 169 is a nickel-based superalloy. Although they all belong to superalloys, the development of powder disk and blade materials is not consistent. FGH95 is the first generation powder disk material in China, and DD3 is the first generation single crystal alloy. The second generation powder disk material GH4 169, and the second generation single crystal alloy DD6. The blade material is oriented crystal DZ4, and the upgraded product is Ni3Al-based DZ6. Then GH4 169 was used to find instability, and then it developed to IC6. At this time, China's single crystal alloy appeared on the blade in black and pink. The requirements for blade materials are higher than those for powder trays, or the most advanced materials are first used in blade materials. From the blade development of WP 13, it can be seen that the materials of high and low pressure turbine blades are inconsistent, and the most advanced materials are first used in high pressure turbine blades. In terms of technical characteristics, the requirements of blades are also different from those of powder trays. In addition, laboratory products are different from industrial products. High-temperature materials need advanced technology to get out of the laboratory. For example, GH4 169 was industrialized in 2000, but it was applied as early as 94 years ago.
Kunlun engine is the first aviation military engine developed according to the model and specification in China, which has completely independent intellectual property rights. It is also the first car to complete the whole process of self-development. The annular combustion chamber with pneumatic atomizing nozzle, composite air-cooled directional solidification precision casting turbine blades without allowance, digital anti-surge control system, compressor high stable gain technology, high-power accessory gearbox and so on are adopted. It is more advanced than J -79 and can be improved into a turbofan engine with small bypass ratio. Designed by Shenyang Engine Design and Research Institute, jointly developed by Liming Aero-Engine Division, Xi 'an Aero-Engine Company and Honglin Machinery Co., Ltd.,/kloc-0 was designed in early 1983, and it was tested in February 1985.1September 1986 reached the design index of the verification machine. The design will be formally finalized on July 9, 2002. In 2000, he won the first prize of scientific and technological progress of China Academy of Sciences, and the project "GH76 1 alloy for Kunlun engine and its application". GH76 1 high strength wrought Fe-Ni-based superalloy has high yield strength, durable strength, cold and hot fatigue resistance and low cycle fatigue resistance, excellent notch performance, and long-term stable microstructure and properties from room temperature to 700℃. A series of technical problems such as segregation, ultrasonic flaw detection, alloy melting, hot working, die forging and ring rolling have been solved. It can be used for high-temperature bearing parts such as turbine disks working below 750℃.
Xinyi machinery factory DZ4, DZ 17G, IC-6, etc. Manufacturing turbine rotors and guide vanes. Using special ceramic core to make cavity, vacuum air quenching heat treatment, strong grinding precision machining, tenon shot peening strengthening, high temperature corrosion-resistant coating on blade body, nondestructive testing, vibration polishing and other manufacturing processes. TC4, TC 1 1, GH4 169, ICr 1 1Ni2W2MoV are used for manufacturing high-pressure air compressor, compressor blade and fan blade, precision forging, vacuum heat treatment, precision machining of tenon and profile, and shot peening of tenon and profile.
China is developing DZ 17G casting alloy K4 169 and single crystal superalloy, as well as long-range ordered intermetallic compounds NiAlNi3al, FeAl, FeAl and TiAl. DZ 125 directionally solidified superalloy can be used as directional thin-walled hollow blades for advanced aero-engines. In 2000, Aeronautical Materials Magazine reported that the thin-walled directional blade with complex inner cavity of an aero-engine passed the bench test and was put into small batch production. The alloy has good directional casting process performance and high thin-wall mechanical properties.
MCrAIY coating containing Y2O3 is the third generation composition designable coating for hot-end parts of engines such as turbine blades and guide vanes, and has been applied in foreign high-performance and long-life engines. The Institute of Aeronautical Materials has successfully developed this kind of coating series by magnetron sputtering deposition process and multi-arc ion plating technology, and its thermal corrosion resistance and comprehensive performance have reached the advanced level of similar coatings abroad. The coating series has been selected by turbine blades and guide blades of superalloys, directionally solidified alloys, single crystal alloys and Ni-A 1 based alloys, and has been used as high-temperature oxidation-resistant coatings on advanced engines and ground gas turbines. NiCrAlY nanocrystalline coating was prepared on the surface of guide blade by sputtering ion plating technology, which can be used as the material of 1 150℃ turbine guide blade and 1050℃ turbine working blade, and began to enter mass production in 2000. The Institute of High-temperature Materials started the research related to the "863" project, and made great progress in the research of intermetallic alloys such as TiAl, Ti2AlNb and Ni3Al. Many important components have been successfully developed for China's aerospace, aviation and weapons departments, and some of them have been successfully tested.
Directionally solidified Ni3Al-based superalloy IC 10 was developed by Beijing Institute of Aeronautical Materials, and was used to braze the guide vanes of advanced engines and GH3039 dissimilar superalloys. After searching, GH3039 is usually used as a diffuser of afterburner. Use electron beam welding or vacuum brazing. China's advanced engines will definitely not use solid solution strengthened nickel-base alloy as combustion chamber components, so it is judged that other engines use IC 10 model.
Tac-1(TiAl24Nb14V3mo0.5) and TAC- 1B were successfully developed by Titanium and Aluminum Center of Beijing Iron and Steel Research Institute. The mechanical properties and technological properties of these two Ti3Al-based alloys are completely superior to those of similar alloys in the United States. TAC- 1 breaks through the technical difficulties such as superplasticity, welding and plate rolling. The temperature range of TAC- 1B is:-100℃ ~ 700℃. TAC- 1 and TAC- 1B alloys have excellent cold and hot workability and mechanical machinability, and can be processed into various profiles such as cakes, bars, tubes, sheets and foils, and have excellent superplastic forming, diffusion bonding and fusion welding properties. They are advanced high-temperature lightweight structural materials with engineering significance and have great potential in aerospace and other fields. Cao et al. of Beihang University chose two vanadium-free Ti3Al alloys, TD3 (Tial24Nb15mo1.5) and TD4 (Tial24Nb13mo1.5Si0.5). Compared with TD2 alloy, TD3 and TD4 have better oxidation resistance, fracture toughness, plasticity and high temperature durability. At present, the combustor cyclone, compressor shell, support ring, combustor and turbine guide plate of gas turbine have been successfully trial-produced with Ti3Al. In recent ten years, the research of 863 intermetallic compound high temperature materials in China has made great progress in solving the brittleness and engineering practicability of Ti3Al and TiAl. Cast TiAl has been successfully developed for components of aero-engine vortex devices and is being used for evaluation. Ni3Al-based MX246 series alloys with independent intellectual property rights developed by Titanium and Aluminum Center of Iron and Steel Research Institute. Specific gravity of 7.9g/cm3, excellent medium and high temperature strength, good room temperature high temperature plasticity, excellent cavitation and ablation resistance, and excellent high temperature oxidation resistance. All the indexes are shown in table 1 ~ 2, and the high-temperature performance is better than that of the traditional superalloy. It has good high-temperature microstructure stability and excellent casting process performance, and is suitable for manufacturing large castings with high cost performance. MX246 series alloys can work stably at 1000 ~ 1200℃ for a long time. At present, the high-temperature bearing components of aero-engines are all large and complicated thin-walled castings, with a wall thickness of 1 ~ 1.2 mm and an outline area of 500× 100mm, which are directly in contact with 1800K high-temperature gas erosion and bear the afterburner of high-temperature flame vector, and work in1for a long time.
The technology of liquid electromagnetic forming and ultra-high gradient ultra-fine directional solidification of special alloy and its intermetallic compound aero-engine blades proposed by Academician Fu Hengzhi is the first in the world. 1994, he led the project of "ultra-high gradient electromagnetic self-restraint directional technology and research on ultra-fine single crystal and directional turbine blades", and initially realized alloy melting and directional solidification without crucible and mold. It is entirely possible to obtain ultra-fine columnar crystal castings (blades) with set shapes by using ultra-high gradient ZMLMC directional solidification technology and introducing electromagnetic self-restraint forming technology, thus realizing ultra-fine directional solidification structure of turbine blades with specific three-dimensional shapes. In this way, directional solidification technology ultra-high gradient electromagnetic self-restraint forming will probably become a new generation of turbine blade preparation technology. Based on the research background of high thrust ultra-high temperature engine, the preparation technology of Ti-Al-based engine blades with heat resistance above 1000℃ was independently developed. The intermetallic compound-based superalloy or composite material with no segregation (less), ultra-fine structure and high precision orientation obtained by single crystal technology with new orientation and ultra-high cooling capacity meets the requirements of turbine blades and guide blades with high thrust-to-weight ratio, long service life and working temperature greater than 1200℃ of a new generation of aero-engines. The research results can be quickly engineered and directly used in the development and production of high-performance aero-engine turbine blades and guide blades.
The broken powder disk with filler at 750℃ is the key material of turbine disk for China 10 engine. The second and third generation single crystal alloys are being developed. The second generation single crystal superalloy DD6 developed by Beijing Institute of Aeronautical Materials is used in advanced turbine engine blades, and it is the single crystal alloy with the best comprehensive properties in China. It is suitable for manufacturing gas turbine blades with complex cavities and high-temperature parts working under high temperature, high stress, oxidation and corrosion conditions. It is completely resistant to oxidation at 1050-400℃, and the corrosion rate is ≤ 0. 18/m2 at 850-1000℃//00h. The tensile strength, durability, oxidation resistance and thermal corrosion resistance of DD6 reach or partially exceed those of the second generation foreign single crystal alloys, and it has the advantage of low cost. According to the research plan of high thrust-to-weight ratio and the requirements of the design department, the High Temperature Materials and Application Laboratory of University of Science and Technology Beijing is filling the gap of domestic advanced turbine disk materials, storing the key technologies of high thrust-to-weight ratio aero-engine materials, carrying out the research on the dual-performance turbine disk of high thrust-to-weight ratio engine powder superalloy in the Tenth Five-Year Plan, and developing the high-performance superalloy disk materials that are difficult to deform at 750-850℃. 863 "Preparation Technology of Rapid Solidification Spray Forming High-melting-point Structural Materials", studies the special microstructure of spray forming high-temperature structural materials and its relationship with high-temperature creep and fatigue properties, laying a foundation for application.
China has been able to produce small and medium-sized titanium alloy blade precision forgings and directional hollow blade precision castings in small batches, and successfully developed single crystal alloy blade precision castings, titanium alloy casing castings with a diameter of 570mm and die forgings with a projection area less than 1m2. There is a big gap with the international advanced level. Compared with the demand for hot working technology in the development and production of advanced fighter planes, advanced civil aircraft and their high thrust-to-weight ratio engines and airborne equipment in China, it is necessary to study the hot isostatic pressing composite forming technology of double-alloy integral bladed disks (single crystal blades and powder disks), the spray forming technology of ultra-pure superalloy turbine disks and related technologies, and the spray forming technology of aluminum-based composite components, so as to make good technical reserves for the development of new machines. Aiming at the industrial production requirements of aircraft and typical engine parts under research, the direct hot isostatic pressing batch production process and its reliability of engine powder alloy turbine disk are studied, and the engineering application of spray forming technology in engine turbine disk is carried out. Concentrate on overcoming the key hot working technologies urgently needed by advanced fighters and advanced civil aircraft and their supporting engines, such as the precision casting technology of efficiently cooling single crystal blades and the superplastic forging technology of powder superalloy turbine disks, so as to ensure the smooth development of new aircraft.
According to the Integrated High Temperature Turbine Gas Turbine Program (IHPTET) and Advanced Heat Engine Materials Program (HITEP) of the United States, the target of ceramic matrix composites is military and civil engines above 1650℃. At present, the development trend of advanced ceramic preparation technology and basic research can be roughly attributed to single crystal and multiphase ceramics, thin film lamination, thin film lamination and multi-layer bulk materials. It is generally considered that C/C composite is the first choice for the engine hot-end components with a thrust-to-weight ratio of 20 ~ 30 at 1930 ~ 2227℃. Its weight is 1/4 of that of superalloy, and its specific strength is five times higher. The development direction is to break through the anti-oxidation coating materials and technologies, and to prepare high-efficiency and low-cost technologies, which will be applied sooner or later.
China has developed a ceramic matrix composite that can work at 1300 degrees Celsius, and its main mechanical properties have reached the international advanced level. Breaking through the key technologies such as near-net-size manufacturing of ceramic matrix composite thin-walled special-shaped structures, full-scale typical specimens, such as floating wall of aero-engine combustion chamber, heat insulation board of vector nozzle regulator, etc., were prepared, and some parts were subjected to environmental simulation tests. At present, the sintering manufacturing technology of large-scale ceramic parts and complex-shaped parts for high temperature, the molding technology of micro-precision ceramic parts and the nondestructive testing technology of internal defects of ceramic parts have been carried out, which has greatly improved the technical level of structural ceramic products in China. The bending strength of 30% Cf/Si3N4 is 454MPa, the KIC is 15.6 MPa m 1/2+0/2, and the fracture work is 4770J/m2, which is obviously better than that of foreign Si3N4 ceramics. The bending strength and KIC of the high melting point intermetallic compound SiCw(20%)/MoSi2 developed in China are 346 MPa and 4.0 1 MPa m 1/2+0/2, respectively. Mo5Si3 is considered as a potential candidate material at high temperature, and its creep performance has exceeded 1300℃. Five kinds of high temperature titanium alloys, Ti-55, Ti-633G, Ti-533 1 1S, 77 15C and HT-5-Y, have been successfully developed in China ... Ti3Al bars and plates have been developed, and φ656mm×506mm×80mm rings have been forged. A new type of high toughness Ti-45 1 alloy, whose fracture toughness is 3 1% higher than that of Ti6Al4V, has been used in aircraft accident recorder shell, bulletproof armor, flame thrower cylinder and so on. China has introduced 6t Al-Li alloy casting production line, and carried out research on rapidly solidified AlFeVSi series, super-crystalline Al-Si series heat-resistant aluminum alloys, fiber and particle reinforced aluminum matrix composites in the 863 Program. In addition, since 1990s, the research and development of advanced magnesium alloys have developed rapidly. KH-304 thermosetting polyimide resin developed and produced by Institute of Chemistry, Chinese Academy of Sciences and KH-304/HT3 composite material developed and produced by Beijing Institute of Materials Technology can withstand 3 17℃ jet engine bypass. There are still obvious gaps in the modification of polymer materials, the development of new special materials, molding technology and equipment, design and product development in China.