Military new materials can be divided into structural materials and functional materials according to their applications, which are mainly used in aviation industry, aerospace industry, weapons industry and ship industry.

aluminium alloy

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

In the aviation industry, aluminum alloy is mainly used to manufacture aircraft skin, spacer frame, long beam and honing bar; In the aerospace industry, aluminum alloy is an important material for carrier rocket and spacecraft structural parts. In the field of weapons, aluminum alloy has been successfully used in infantry combat vehicles and armored transport vehicles. Recently, a large number of new aluminum alloy materials have been used in the artillery racks of howitzers.

magnesium alloy

As the lightest engineering metal material, magnesium alloy has a series of unique properties, such as light specific gravity, high specific strength and specific stiffness, good damping and thermal conductivity, strong electromagnetic shielding capability, 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, gunner's mirror, gearbox box, engine filter seat, water inlet and outlet pipe, air distributor seat, oil pump housing, water pump housing, oil heat exchanger, oil filter housing, valve cover, respirator and other vehicle parts; Support cabin section of tactical air defense missile, aileron skin, wallboard, reinforcing frame, rudder plate, spacer frame and other missile parts; Fighters, bombers, helicopters, transport planes, airborne radars, ground to air missiles, carrier rockets, artificial satellites and other spacecraft and aircraft components. Magnesium alloy has the characteristics of light weight, good specific strength and stiffness, good damping performance, strong electromagnetic interference and 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 aerospace and national defense construction, and is the key structural material required by aircraft, satellites, missiles, fighter planes, combat vehicles and other weapons and equipment.

titanium alloy

Titanium alloy has high tensile strength (441~1470MPa) and low density (4.5g/cm 3）， It is an ideal lightweight structural material with excellent corrosion resistance, certain high temperature endurance strength and good low temperature impact toughness at 300~550 ℃. Titanium alloy has the function of superplasticity. using superplastic forming diffusion bonding technology, the alloy can be made into products with complex shape and precise size with little energy consumption and material consumption.

The application of titanium alloy in the aviation industry is mainly to make aircraft fuselage structure, landing gear, support beam, engine compressor disk, blade and joint, etc; In the aerospace industry, titanium alloys are mainly used to make load-bearing components, frames, gas cylinders, pressure vessels, turbine pump shells, solid rocket motor shells, nozzles and other parts.

compound material

Resin matrix composites, metal matrix composites, ceramic matrix composites, carbon carbon composites

Ultra high strength steel

Ultra high strength steel is a steel whose yield strength and tensile strength exceed 1200 MPa and 1400 MPa respectively. It is researched and developed to meet the requirements for materials with high specific strength on aircraft structures. Due to the expansion of the application of titanium alloy and composite materials in aircraft, the amount of steel used in aircraft has decreased, but the key load-bearing components of aircraft are still made of ultra-high strength steel. At present, the internationally representative low alloy ultra-high strength steel 300M is a typical steel for aircraft landing gear. 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 continuously improve the toughness and stress corrosion resistance while ensuring ultra-high strength.

Advanced superalloy

Superalloys are the key materials for aerospace power systems. Superalloy is an alloy that can withstand certain stress at 600~1200 ℃ and has the ability of oxidation resistance and corrosion resistance. It is the preferred material for turbine disk of aerospace engine. According to different matrix components, superalloys can be divided into three categories: iron base, nickel base and cobalt base. The engine turbine disk was made of forged superalloy before the 1960s, with typical brands of A286 and Inconel 718. In the 1970s, GE made the turbine disk of CFM56 engine with rapidly solidified powder Rene95 alloy, greatly increasing its thrust weight ratio and operating temperature. Since then, powder metallurgy turbine disk has developed rapidly. Recently, compared with powder superalloy, the superalloy turbine disk manufactured by spray deposition rapid solidification process in the United States has simple process, low cost, good forging performance and great development potential.

tungsten alloy

The melting point of tungsten is the highest among metals. Its outstanding advantage is that the high melting point brings good high temperature strength and corrosion resistance of materials. It has shown excellent characteristics in military industry, especially in weapon manufacturing. In the weapons industry, it is mainly used to make various armour piercing warheads. Through powder pretreatment technology and large deformation strengthening technology, tungsten alloy can refine the grain of the material and elongate the grain orientation, so as to improve the strength, toughness and penetration power of the material. The tungsten core material of the main battle tank 125 Ⅱ armor piercing projectile developed in China is W-Ni-Fe. The variable density compact sintering process is adopted. The average performance reaches the tensile strength of 1200 MPa, the elongation is more than 15%, and the combat technical index is to break through 600 mm thick homogeneous steel armor at a distance of 2000 meters. At present, tungsten alloys are widely used in the core materials of armor piercing projectiles with large length to diameter ratio, small and medium caliber air defense armor piercing projectiles and hypervelocity kinetic energy armor piercing projectiles for main battle tanks, which makes various armor piercing projectiles have more powerful puncture power.

Source: Material Heat Treatment Engineer