Application de nouveaux matériaux militaires et tendances de développement dans ce domaine

Material technology has always been a very important field in the scientific and technological development planning of all countries in the world. Together with information technology, biotechnology and energy technology, it is recognized as the high technology that will take over the whole human situation in today's society and in the future for a long time. High technology of materials is also the key technology of modern industry that supports today's human civilization. It is also the most important material foundation of a country's national defense force. The national defense industry is often the preferred user of new material technology, and the research and development of new material technology plays a decisive role in the development of the national defense industry and weapons and equipment.

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The strategic significance of new materials for military use
New military materials are the material basis of the new generation of weapons and equipment, and also the key technology in the world military field. The military new material technology is the new material technology used in the military field, is the key of modern sophisticated weapons and equipment, is an important part of military high technology. All countries in the world attach great importance to the development of new military material technology. Accelerating the development of new military material technology is an important premise to keep the military lead.

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Application status of new materials for military use
According to their uses, new military materials can be divided into structural materials and functional materials, which are mainly used in aviation industry, aerospace industry, ordnance industry and ship industry.


Military structural material
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Aluminium alloy

Aluminum alloy has been the most widely used metal structural material in military industry. Aluminum alloy has the characteristics of low density, high strength, good processing performance and so on. As a structural material, because of its excellent processing performance, it can be made into various sections of profiles, pipes, high reinforcement plates, etc., in order to give full play to the potential of materials, improve the stiffness and strength of components. Therefore, aluminum alloy is the preferred lightweight structural material for weapon lightweight.

Aluminum alloy in the aviation industry is mainly used in the manufacture of aircraft skin, frame, long beam and headway; In the aerospace industry, aluminum alloy is an important material for the structural parts of carrier rockets and spacecraft. In the field of weapons, aluminum alloy has been successfully used in infantry fighting vehicles and armored transport vehicles, and the recently developed howitzer gun rack also uses a large number of new aluminum alloy materials.

The use of aluminum alloy in the aerospace industry has decreased in recent years, but it is still one of the main structural materials in the military industry. The development trend of aluminum alloy is to pursue high purity, high strength, high toughness and high temperature resistance. Aluminum alloy used in military industry mainly includes aluminum lithium alloy, aluminum copper alloy (2000 series) and aluminum zinc magnesium alloy (7000 series).

The new aluminum lithium alloy applied in the aviation industry is predicted to reduce the weight of aircraft by 8 to 15 percent. Aluminum-lithium alloys will also be candidate structural materials for aerospace vehicles and thin-walled missile casings. With the rapid development of the aerospace industry, the focus of Al-Li alloy research is still to solve the problem of toughness and cost reduction in the thickness direction.

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Magnesium alloy

As the lightest engineering metal material, magnesium alloy has a series of unique properties, such as light specific weight, high specific strength and stiffness, good damping and thermal conductivity, strong electromagnetic shielding ability, and good vibration damping, which greatly meet the needs of aerospace, modern weapons and equipment and other military fields.

Magnesium alloy has many applications in military equipment, such as tank seat frame, vehicle length mirror, gun length mirror, transmission box, engine filter seat, inlet and outlet water pipe, air distributor seat, oil pump housing, water pump housing, oil heat exchanger, oil filter housing, valve chamber cover, breathing apparatus and other vehicle parts. The supporting cockpit segment, aileron skin, wall panel, stiffener frame, rudder plate, baffle frame and other missile and arrow parts of tactical air defense missile; Fighter aircraft, bombers, helicopters, transport aircraft, airborne radar, ground-to-air missiles, carrier rockets, satellites and other spacecraft aircraft components. Magnesium alloy has the advantages of light weight, good specific strength and stiffness, good vibration damping performance, electromagnetic interference and strong shielding ability, which can meet the requirements of military products for weight reduction, noise absorption, shock absorption and radiation protection. It plays a very important role in the construction of aerospace and national defense. It is the key structural material for aircraft, satellites, missiles, fighter jets and fighting vehicles and other weapons and equipment.

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Titanium alloy

Titanium alloy is an ideal lightweight structural material with high tensile strength (441~1470MPa), low density (4.5g/cm³), excellent corrosion resistance and a certain high temperature lasting strength and good low temperature impact toughness at 300~550℃. Titanium alloy has the function of superplasticity. By using the superplastic shape-diffusion connection technology, the alloy can be made into products with complex shape and precise size with little energy and material consumption.

The application oftitanium-alloy.html> titanium alloy in the aviation industry is mainly the production of aircraft fuselage structure parts, landing gear, support beam, engine compressor disc, blades and joints; In the space industry, titanium alloy is mainly used to make load-bearing components, frames, cylinders, pressure vessels, turbopump shells, solid rocket motor shells and nozzle parts. In the early 1950s, in some military aircraft began to use industrial pure titanium manufacturing of the rear fuselage of the heat shield, tail cover, speed plate and other structural parts; In the 1960s, the application of titanium alloy in aircraft structures was expanded to flap sliding, bearing frame, landing gear beam and other major stress structures. Since 1970s, the use of titanium alloy in military aircraft and engines has increased rapidly, expanding from fighter aircraft to military large bombers and transport aircraft. Its use in F14 and F15 aircraft accounts for 25% of the structural weight, and in F100 and TF39 engines, 25% and 33% respectively. After the 1980s, titanium alloy materials and process technology reached further development, a B1B aircraft needs 90402 kg titanium material. Among the existing aerospace titanium alloys, the most widely used is the multipurpose a+b Ti-6Al-4V alloy. In recent years, the West and Russia have developed two new titanium alloys, they are high strength and high toughness welding and good formability of titanium alloys and high temperature and high strength flame retardant titanium alloys, these two advanced titanium alloys have good application prospects in the future aerospace industry.

With the development of modern warfare, the army forces need the advanced howitzer system with high power, long range, high precision and rapid response. One of the key technologies of advanced howitzer system is new material technology. It is an inevitable trend of weapon development for self-propelled gun turret, component and light metal armored vehicle to use lightweight materials. Titanium alloy is widely used in army weapons to ensure dynamic and protective conditions. 155 fire processing detractor using titanium alloy can not only reduce the weight, but also reduce the deformation of the gun barrel due to gravity, effectively improve the shooting accuracy; Some complex components of main battle tanks and helicopter-anti-tank multipurpose missiles can be made of titanium alloy, which can not only meet the performance requirements of products but also reduce the machining cost of components.

For a long time in the past, the application of titanium alloy was greatly limited due to its high manufacturing cost. In recent years, countries around the world are actively developing low cost titanium alloy, while reducing the cost, but also improve the performance of titanium alloy. In our country, the manufacturing cost of titanium alloy is still relatively high, with the gradual increase of titanium dosage, seeking lower manufacturing cost is the inevitable trend of the development of titanium alloy.

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Composite material

4.1 Resin-based composite materials

Resin matrix composites have good forming process, high specific strength, high specific modulus, low density, fatigue resistance, shock absorption, chemical corrosion resistance, good dielectric properties, low thermal conductivity and other characteristics, widely used in the military industry. Resin matrix composites can be divided into thermosetting and thermoplastic. Thermosetting resin matrix composite is a kind of composite material which is composed of various thermosetting resins as matrix and various reinforced fibers. The thermoplastic resin is a class of linear polymer compounds, it can be dissolved in solvent, can also be softened and melted into a viscous liquid when heating, hardening into a solid after cooling. Resin matrix composites have excellent comprehensive properties, easy preparation and abundant raw materials. In the aviation industry, resin-based composites are used to make aircraft wings, fuselages, canards, flat tails and engine outsides. In the field of aerospace, resin matrix composite material is not only an important material for rudder, radar and inlet, but also can be used to make the adiabatic shell of solid rocket engine combustion chamber, and also can be used as the ablative heat protection material for engine nozzle. The new cyanic acid resin composites developed in recent years have the advantages of strong moisture resistance, good microwave dielectric properties, good dimensional stability, etc., and are widely used in the manufacture of aerospace structural parts, aircraft primary and secondary bearing structural parts and radar radome.

4.2 Metal matrix composite materials
Metal matrix composites with high specific strength, high specific modulus, good high temperature performance, low coefficient of thermal expansion, good dimensional stability, excellent electrical and thermal conductivity have been widely used in the military industry. Aluminum, magnesium and titanium are the main matrix of metal matrix composite materials, and reinforcement materials can be generally divided into fiber, particle and whisker three categories, among which particle reinforced aluminum matrix composite materials have entered the model verification, for example, used in F-16 fighter jets as a pelvic fin instead of aluminum alloy, its stiffness and life are greatly improved. Carbon fiber reinforced aluminum and magnesium matrix composites have high specific strength, close to zero coefficient of thermal expansion and good dimensional stability, and have been successfully used in the manufacture of satellite support, L band plane antenna, space telescope, satellite paraboloid antenna, etc. Silicon carbide particle reinforced aluminum matrix composite material has good high temperature performance and anti-wear characteristics, can be used in the production of rocket, missile components, infrared and laser guidance system components, precision avionics devices, etc. Silicon carbide fiber reinforced titanium matrix composite has good high temperature resistance and oxidation resistance. It is an ideal structural material for high thrust-weight ratio engine and has entered the trial stage of advanced engine. In the field of ordnance industry, metal matrix composite materials can be used in large caliber tail stabilizer shell shell, anti-helicopter/anti-tank multi-purpose missile solid motor shell and other parts, so as to reduce the weight of warhead, improve combat ability.

4.3 Ceramic matrix composite materials

Ceramic matrix composite is a general term for the materials composed of fiber, whisker or particle as the reinforcement body and ceramic matrix combined with a certain composite process. It can be seen that ceramic matrix composite is a multiphase material composed of the second phase component introduced into the ceramic matrix, which overcomes the inherent brittleness of ceramic materials and has become one of the most active aspects in the current material science research. Ceramic matrix composite is one of the key supporting materials for the future development of military industry because of its low density, high specific strength, good thermal mechanical properties and thermal shock resistance. The high temperature performance of ceramic material is good, but its brittleness is great. The methods to improve the brittleness of ceramic materials include phase change toughening, microcrack toughening, dispersion metal toughening and continuous fiber toughening. Ceramic matrix composites are mainly used to make jet nozzle valves of aircraft gas turbine engines, which play an important role in improving thrust-weight ratio and reducing fuel consumption.

4.4 Carbon-carbon composite materials
Carbon - carbon composite is composed of carbon fiber reinforcing agent and carbon matrix. Carbon - carbon composites have a series of advantages such as high specific strength, good thermal shock resistance, strong ablative resistance and designable performance. The development of carbon - carbon composites is closely related to the demanding requirements of aerospace technology. Since 1980s, the research of carbon - carbon composites has entered the stage of improving performance and expanding application. In the military industry, the most notable use of carbon-carbon composites is in the space shuttle's antioxidant carbon-carbon nose cone caps and wing leading edges, and the largest use of carbon-carbon products is in the brake pads of supersonic aircraft. In aerospace, carbon-carbon composites are mainly used as ablative materials and thermal structural materials. Specifically, they are used as nose cone caps for intercontinental missile warheads, solid rocket nozzles and leading edges of space shuttle wings. Current advanced carbon-carbon nozzles have densities of 1.87~1.97 g/cc and toroidal tensile strength of 75~115 mpa. The end caps of the recently developed long-range intercontinental missiles are almost all made of carbon-carbon composite materials.

With the development of modern aviation technology, the loading mass of aircraft is increasing and the landing speed is increasing, which puts forward higher requirements for emergency braking of aircraft. Carbon-carbon composite material is light in weight, high temperature resistance, high energy absorption, good friction performance, it is widely used in high speed military aircraft brake pads.

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Composite ultra-high strength steel

Ultra high strength steel is steel with yield strength and tensile strength exceeding 1200 mpa and 1400 mpa, respectively. It is researched and developed to meet the requirements of high specific strength materials in aircraft structure. The use of steel in aircraft has decreased due to the expansion of titanium alloy and composite materials, but the key load-bearing components of aircraft are still made of ultra-high strength steel. At present, the international representative low-alloy ultra-high strength steel 300M, is a typical aircraft landing gear steel. In addition, low alloy ultra high strength steel D6AC is a typical solid rocket motor housing material. The development trend of ultra-high strength steel is to improve the toughness and stress corrosion resistance while ensuring ultra-high strength.

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Advanced high-temperature metal

Superalloy is the key material of aerospace power system. Superalloy is a kind of alloy which can withstand certain stress at high temperature of 600~1200℃ and has oxidation and corrosion resistance. It is the preferred material for turbine disk of aerospace engine. According to the different matrix components, superalloy is divided into iron base, nickel base and cobalt base three categories. Engine turbine discs were made of forged superalloys until the 1960s, typical grades being A286 and Inconel 718. In the 1970s, GE made CFM56 engine turbine disc with fast solidifying powder Rene95 alloy, which greatly increased its thrust-weight ratio and service temperature. Since then, powder metallurgy turbine disks have developed rapidly. Recently, the superalloy turbine disk manufactured by the rapid solidification process of jet deposition in the United States is a kind of preparation technology with great potential for development. Compared with powder superalloy, the superalloy turbine disk has the advantages of simple operation, lower cost and good forging and machining performance.

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Tungsten alloy

Tungsten has the highest melting point among metals, and its outstanding advantage is that high melting point brings good high temperature strength and corrosion resistance of the material, which shows excellent characteristics in military industry, especially in weapon manufacturing. In the ordnance industry, it is mainly used to make a variety of armor-piercing warheads. The grain size of tungsten alloy is refined and the orientation of grain is elongated by powder pretreatment and large deformation strengthening technology, so as to improve the strength, toughness and penetration power of the material. The tungsten core material of Type 125II armor penetrator for the main battle tank is W-Ni-Fe, and the average performance of the tungsten core is 1200 mpa, the elongation is more than 15%, and the technical index is 600 mm thick uniform steel armor at 2000 meters. At present, tungsten alloy is widely used in the core materials of large aspect ratio armor-piercing shells, medium and small caliber anti-aircraft armor-piercing shells and ultra-high speed kinetic energy armor-piercing shells for main battle tanks, which makes all kinds of armor-piercing shells have more powerful breakdown power.

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Intermetallic compound

Intermetallic compounds have long range ordered superlattice structure, and maintain strong metal bonding, which gives them many special physical and chemical properties and mechanical properties. Intermetallic compounds with excellent thermal strength have become important new high temperature structural materials in recent years. In the military industry, intermetallic compounds have been used in the manufacture of parts that bear thermal loads, such as the JT90 gas turbine engine blades manufactured by Pu 'ao Company in the United States, the rotor blades of small aircraft engines made of titanium and aluminum by the United States Air Force, etc. Russia uses titanium and aluminum intermetallic compounds instead of heat-resistant alloys as piston tops, greatly improving the performance of engines. In the field of ordnance industry, the tank engine supercharger turbine material is K18 nickel-based superalloy, because of its large ratio, large starting inertia and affect the acceleration performance of the tank, the application of titanium aluminum intermetallic compound and its aluminum oxide, silicon carbide fiber reinforced composite light heat resistant new material, can greatly improve the tank starting performance, improve the battlefield survivability. In addition, intermetallic compounds can be used in a variety of heat-resistant components, reducing weight, improving reliability and technical performance.

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Structural ceramics

Ceramic materials are the fastest developing high-tech materials in the world. It has developed from single-phase ceramics to multiphase composite ceramics. Structural ceramic materials have good application prospects in military industry because of their excellent properties such as high temperature resistance, low density, wear resistance and low coefficient of thermal expansion.

In recent years, a wide range of structural ceramics for military engines have been studied at home and abroad. For example, the small turbocharger has been put into practice. In the United States, ceramic plates are embedded on the top of the piston, which greatly improves the service life of the piston and also improves the thermal efficiency of the engine. German exhaust port inlaid ceramic components, improve the use of exhaust port efficiency. The piston sleeve and cylinder sleeve of the micro Stirling refrigerator on the foreign infrared thermal imager are made of ceramic material, and its life is as long as 2000 hours. The power supply of the gyroscope for missile depends on gunpowder gas, but the gunpowder residue in the gas has serious damage to the gyroscope. In order to eliminate the residue in the gas and improve the hit accuracy of the missile, it is necessary to study the ceramic filter material suitable for the missile gunpowder gas working at 2000℃. In the field of weapon industry, structural ceramics are widely used in turbocharger turbine, piston top and exhaust port inlaid block of main battle tank engine, and are the key materials of new weapon equipment. At present, the RF requirement of 20~30 mm caliber machine gun is more than 1200 rounds/min, which makes the ablative of the gun barrel extremely serious. The high melting point and high temperature chemical stability of the ceramic can effectively restrain the serious ablative of the gun tube. The ceramic material has high compressive and creep resistance characteristics. Through reasonable design, the ceramic material can keep the three-way compression state, overcome its brittleness, and ensure the safe use of the ceramic liner.

Military functional material
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Photoelectric functional material

Photoelectric functional material refers to the material used in optoelectronic technology, it can combine photoelectric information transmission and processing, is an important part of modern information technology. Photoelectric functional materials are widely used in military industry. Mercury cadmium telluride and indium antimonide are important materials for infrared detectors. Zinc sulfide, zinc selenide, gallium arsenide are mainly used in the production of aircraft, missiles and ground weapons equipment infrared detection system window, hood, fairing, etc. Magnesium fluoride has high transmittance, strong resistance to rain erosion and erosion, and it is a good infrared transmission material. Laser crystal and laser glass are high power and high energy solid laser materials, typical laser materials include ruby crystal, neodymium-doped yttrium aluminum garnet, semiconductor laser materials and so on.

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Hydrogen storage material

Due to the special lattice structure of some transition cluster metals, alloys and intermetallic compounds, hydrogen atoms are easier to penetrate into the tetrahedral or octahedral interstitial sites of the metal lattice, forming metal hydrides, which are called hydrogen storage materials.

In the ordnance industry, the lead-acid batteries used in tanks and vehicles need to be charged frequently because of their low capacity and high self-discharge rate. The discharge output power is easily affected by the battery life, charging state and temperature. In cold climate, the starting speed of the tank will be significantly slowed down, or even can not start, which will affect the combat ability of the tank. Hydrogen storage alloy battery has the advantages of high energy density, overcharge resistance, earthquake resistance, good low temperature performance, long life, etc., and has broad application prospects in the future development of main battle tank battery.

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Damping material

Damping refers to the phenomenon that the mechanical properties of a freely vibrating solid will be converted into heat energy even if it is completely isolated from the outside world. The purpose of using high damping functional materials is to reduce vibration and noise. Therefore, damping damping material is of great significance in military industry.

The applications of metal damping materials are mainly concentrated in shipbuilding, aviation and aerospace industries. The United States Navy has used Mn-Cu high damping alloy to manufacture submarine propeller, which has obtained obvious damping effect. In the west, the research on the application of damping materials and technology in weapons has received great attention. Some developed countries have set up special research institutions on the application of damping materials in weapons and equipment. After the 1980s, foreign damping damping and noise reduction technology has had greater development, they use CAD/CAM in the application of vibration and noise reduction technology, design - material - process - test integration, carried out the overall structure of the damping vibration and noise reduction design. In the 1970s, the research of damping and noise reduction material was carried out in our country, and some achievements were made, but there is still a certain gap compared with the developed countries. Damping material in the field of aerospace is mainly used in the manufacture of rocket, missile, jet and other control panel or gyroscope shell; In the Marine industry, damping materials are used in the manufacture of thrusters, transmission components and cabin partitions, effectively reducing the vibration and noise caused by surface collisions during the meshing of mechanical parts. In the ordnance industry, the vibration of tank transmission (transmission box) is a complex vibration with a wide frequency range. The application of high-performance damping zinc-aluminum alloy and anti-vibration wear-resistant surface cladding material technology greatly reduces the vibration and noise generated by the transmission part of the main battle tank.

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Stealth material

The development of modern attack weapons, especially the appearance of precision attack weapons, has greatly threatened the survival of weapons and equipment, and it is no longer practical to rely solely on strengthening the protective ability of weapons. Stealth technology is adopted to make the enemy's detection, guidance and reconnaissance systems lose their effectiveness, so as to conceal themselves as much as possible and seize the initiative in the battlefield. Preemptive detection and destruction of the enemy has become an important development direction of modern weapon protection. The most effective means of stealth technology is the use of stealth materials. Foreign stealth technology and material research began during the Second World War, originated in Germany, developed in the United States and extended to Britain, France, Russia and other advanced countries. Currently, the United States is leading the way in stealth technology and materials research. In the field of aviation, many countries have successfully applied stealth technology to aircraft stealth. In the aspect of conventional weapons, the United States has also carried out a lot of work on tank and missile stealth, and has been used in equipment, such as the United States M1A1 tank with radar wave and infrared wave stealth materials, the former Soviet Union T-80 tank also coated with stealth materials.

Stealth materials include millimeter wave structure absorbing materials, millimeter wave rubber absorbing materials and multifunctional absorbing coatings. They can not only reduce the detection, tracking and hit probability of millimeter wave radar and millimeter wave guidance system, but also can be compatible with visible light, near infrared camouflage and middle and far infrared thermal camouflage effects.

In recent years, while improving the traditional stealth materials, foreign countries are committed to the exploration of a variety of new materials. Whisker materials, nanomaterials, ceramic materials, chiral materials, conductive polymer materials and so on are gradually applied to radar wave and infrared stealth materials, making the coating thinner and lighter. Nanomaterials are used as a new generation stealth material in developed countries because of their excellent wave-absorbing properties, wide band, good compatibility and thin thickness. The domestic research on millimeter wave stealth materials started in the mid-1980s, and the research units mainly focus on weapon system. After years of efforts, great progress has been made in pre-research, and the technology can be used for camouflage and stealth of various ground-based weapon systems, such as main battle tanks, 155mm advanced howitzer systems and amphibious tanks.

At present, the world is developing the fourth generation of supersonic fighter aircraft, its body structure uses composite materials, wing body fusion body and absorbing coating, so that it really has the stealth function, and electromagnetic wave absorption coating, electromagnetic shielding coating has begun to be painted on the stealth aircraft. American and Russian surface-to-air missiles are using lightweight, wide-band absorbent, heat-stable stealth materials. It can be predicted that the research and application of stealth technology has become one of the most important subjects of national defense technology in the world.

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Development trend of our military new material
The new materials used in military industry have high technical content, so the industrialization speed of new materials for military use is generally slow. The world's new military materials are developing in the direction of functional, ultra-high energy, composite lightweight and intelligent. Therefore, titanium alloy, composite materials and nanomaterials have a very good industrialization prospect in the military industry.

1. Titanium alloy

Titanium is a kind of metal with excellent properties and abundant resources developed in the 1950s. With the increasingly urgent demand for high strength and low density materials in military industry, the industrialization of titanium alloy has accelerated significantly. In foreign countries, the weight of titanium material in advanced aircraft has reached 30~35% of the total weight of the aircraft structure. During the Ninth Five-Year Plan period, in order to meet the needs of aviation, aerospace, naval vessels and other sectors, the country takes titanium alloy as one of the development priorities of new materials. It is expected that the Tenth Five-Year Plan period will become a period of rapid development of new materials and new processes of titanium alloy.

2. Composite materials

The development of military high technology requires that the material is no longer a single structural material. Under such conditions, our country has made great progress in the development and application of advanced composite materials, and its development during the "Tenth Five-Year Plan" will be more noticeable. In the 21st century, the development direction of composite materials is low cost, high performance, multi-function and intelligence.

3. Nanomaterials

Nanotechnology is the product of the combination of modern science and technology. It not only involves all the existing basic science and technology fields, but also has a wide application prospect in military industry. With the sudden increase of future war, various detection means are more and more advanced. In order to meet the needs of modern war, stealth technology plays a very important role in the military field. Nanomaterials have a high absorptivity of radar waves, which provides a material basis for the development of weapon stealth technology.