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Materials used for the manufacture of bulletproof vests. Reservation of modern domestic tanks Composite armor of tanks

Aluminum Composite Armor

Ettore di Russo

Professor Di Russo is the scientific director of the company "Aluminia", which is part of the Italian MCS group of the EFIM consortium.

Alumina, part of the Italian MCS group, has developed a new type of composite armor plate suitable for use on light armored combat vehicles (AFV). It consists of three main layers of aluminum alloys of different composition and mechanical properties, joined together into one plate by means of hot rolling. This composite armor provides better ballistic protection than any standard monolithic aluminum alloy armor currently in use: aluminium-magnesium (5XXX series) or aluminium-zinc-magnesium (7XXX series).

This armor provides a combination of hardness, toughness and strength, which provides high resistance to ballistic penetration of kinetic projectiles, as well as resistance to the formation of armor spalls from the rear surface in the area of ​​impact. It can also be welded using conventional inert gas arc welding techniques, making it suitable for the manufacture of elements of armored combat vehicles.

The central layer of this armor is made of aluminum-zinc-magnesium-copper alloy (Al-Zn-Mg-Cu), which has high mechanical strength. The front and back layers are made of a weldable high-impact Al-Zn-Mg alloy. Thin layers of commercially pure aluminum (99.5% Al) are added between the two internal contact surfaces. They provide better adhesion and increase the ballistic properties of the composite board.

Such a composite structure made it possible for the first time to use a very strong Al-Zn-Mg-Cu alloy in a welded armor structure. Alloys of this type are commonly used in aircraft construction.

The first lightweight material widely used as armor protection in the design of armored personnel carriers, for example, M-113, is the non-heat treatable Al-Mg alloy 5083. Three-component Al-Zn-Mg alloys 7020, 7039 and 7017 represent the second generation of light armor materials . Typical examples of the use of these alloys are: English cars "Scorpio", "Fox", MCV-80 and "Ferret-80" (alloy 7017), French AMX-10R (alloy 7020), American "Bradley" (alloys 7039+ 5083) and Spanish BMR -3560 (alloy 7017).


The strength of Al-Zn-Mg alloys obtained after heat treatment is much higher than the strength of Al-Mg alloys (for example, alloy 5083), which cannot be heat treated. In addition, the ability of Al-Zn-Mg alloys, unlike Al-Mg alloys, to precipitation hardening at room temperature makes it possible to largely restore the strength that they can lose when heated during welding.

However, the higher penetration resistance of Al-Zn-Mg alloys is accompanied by their increased tendency to armor spalling due to lower impact strength.

A composite three-layer board, due to the presence of layers with different mechanical properties in its composition, is an example of an optimal combination of hardness, strength and impact strength. It has the commercial designation Tristrato and is patented in Europe, USA, Canada, Japan, Israel and South Africa..

Fig.1.

Right: Tristrato armor plate example;

left: cross section showing the Brinell hardness (HB) of each layer.


Ballistic performance

Plates have been tested at several military training grounds in Italy and abroad Tristrato thickness from 20 to 50 mm by shelling with various types of ammunition (various types of 7.62-, 12.7-, and 14.5-mm armor-piercing bullets and 20-mm armor-piercing projectiles).

During the tests, the following indicators were determined:

at various fixed impact velocities, the values ​​of the meeting angles corresponding to the penetration frequencies of 0.50 and 0.95 were determined;

at various fixed angles of impact, impact velocities were determined corresponding to a penetration frequency of 0.5.

For comparison, parallel tests were carried out on monolithic control plates made of alloys 5083, 7020, 7039 and 7017. The test results showed that the armor plate Tristrato provides increased resistance to penetration by selected armor-piercing weapons with a caliber of up to 20 mm. This allows a significant reduction in weight per unit of protected area compared to traditional monolithic slabs while maintaining the same resistance. For the case of shelling with 7.62-mm armor-piercing bullets at a meeting angle of 0 °, the following reduction in mass is provided, which is necessary to ensure equal durability:

by 32% compared to alloy 5083

by 21% compared to alloy 7020

by 14% compared to alloy 7039

by 10% compared to alloy 7017

At a meeting angle of 0 o, the impact velocity corresponding to a penetration frequency of 0.5 increases by 4 ... -but effective against 20mm projectiles FSP , when shelled by which the specified characteristic increases by 21%.

The increased resistance of the Tristrato plate is explained by the combination of high resistance to the penetration of a bullet (projectile) due to the presence of a solid central element with the ability to hold fragments that occur when the central layer is pierced with a plastic back layer, which itself does not give fragments.

Plastic layer on the back Tristrato plays an important role in preventing armor spalling. This effect is enhanced by the possibility of delamination of the plastic back layer and its plastic deformation over a large area in the area of ​​impact.

It is an important mechanism for resisting slab penetration. Tristrato . The peeling process absorbs energy, and the void formed between the core and back member can trap the projectile and fragments generated when the highly hard core material breaks. Likewise, delamination at the interface between the front (face) element and the center layer can contribute to the destruction of the projectile or direct the projectile and fragments along the interface.


Fig.2.

Left: Schematic showing the chipping resistance mechanism of a Tristrate plate brow;

right: the results of a blow with a blunt-nosed armor-piercing

projectile on a thick Tristrato slab;


Production properties

Tristrato slabs can be welded using the same methods that are used to join traditional monolithic slabs of Al-Zn-Mg alloys (methods TIG and MIG ). The structure of the composite plate still requires that some specific measures be taken, determined by the chemical composition of the central layer, which should be considered as a "not good for welding" material, in contrast to the front and back elements. Therefore, when developing a welded joint, one should take into account the fact that the main contribution to the mechanical strength of the joint should be made by the outer and back elements of the plate.

The geometry of welded joints should localize welding stresses along the boundary and in the fusion zone of the deposited and base metals. This is important for solving the problems of corrosion cracking of the outer and back layers of the slab, which is sometimes found in Al-Zn-Mg alloys. The central element, due to its high copper content, exhibits high resistance to stress corrosion cracking.

Rrof. ETTORE DI RUSSO

ALUMINUM COMPOSITE ARMOR.

INTERNATIONAL DEFENSE REVIEW, 1988, No12, p.1657-1658

  • Combined armor, also composite armor, less commonly multi-layer armor is a type of armor consisting of two or more layers of metallic or non-metallic materials. "A passive defense system (design) containing at least two different materials (excluding air gaps) designed to provide balanced protection against cumulative and kinetic munitions used in the ammunition of one high-pressure gun."

    In the post-war period, the main means of defeating heavy armored targets (main battle tank, MBT) became cumulative weapons, represented primarily by dynamically developing anti-tank guided missiles (ATGMs) in the 1950-1960s, the armor-piercing ability of combat units of which by the beginning 1960s exceeded 400 mm of armor steel.

    The answer to parry the threat from cumulative weapons was found in the creation of multi-layer combined armor with a higher, compared to homogeneous steel armor, anti-cumulative resistance, containing materials and design solutions that together provide an increased jet-extinguishing ability of armor protection. Later, in the 1970s, armor-piercing feathered sabots of 105 and 120 mm tank guns with a heavy alloy core were adopted and widely used in the West, providing protection against which turned out to be a much more difficult task.

    The development of combined armor for tanks was started almost simultaneously in the USSR and the USA in the second half of the 1950s and was used on a number of experimental US tanks of that period. However, among production tanks, combined armor was used on the Soviet T-64 main battle tank, whose production began in 1964, and was used on all subsequent main battle tanks of the USSR.

    On serial tanks of other countries, combined armor of various schemes appeared in 1979-1980 on the Leopard 2 and Abrams tanks and since the 1980s has become the standard in world tank building. In the United States, combined armor for the armored hull and turret of the Abrams tank, under the general designation "Special Armor", reflecting the secrecy of the project, or "Burlington", was developed by the Ballistic Research Laboratory (BRL) by 1977, included ceramic elements, and was designed to protect against cumulative ammunition (equivalent thickness for steel no worse than 600 ... 700 mm), and armor-piercing finned shells of the BOPS type (equivalent thickness for steel no worse than 350 ... mass in comparison with equally resistant steel armor, and on later serial modifications it was consistently increased. Due to the high cost compared to homogeneous armor and the need to use armor barriers of great thickness and mass to protect against modern cumulative ammunition, the use of combined armor is limited to main battle tanks and, less often, main or mounted additional armor for infantry fighting vehicles and other light category armored vehicles.

Related concepts

A cumulative-fragmentation projectile (KOS, sometimes also called a multifunctional projectile) is a main-purpose artillery ammunition that combines a pronounced cumulative and weaker high-explosive fragmentation action.

Armored shield - a protective device mounted on a weapon (for example, a machine gun or a gun). Used to protect the gun crew from bullets and shrapnel. Also called an armor shield is a device made from improvised materials, sometimes used in the field to protect the shooter from fire.

Multi-barreled layout - a type of armored vehicle layout scheme, in which the main armament of an armored vehicle unit includes more than one cannon, gun or mortar, or one or more multi-barreled artillery systems (not counting additional barreled weapons, such as machine guns of various types or externally mounted recoilless rifles). Due to a number of reasons of a technical and technological nature, a multi-barrel layout is used mainly in the creation of self-propelled ...

Armored (protective) window - a translucent structure that protects people and material assets in the room from damage or penetration from the outside through the window opening.

Gusmatik, or gusmatic tire - a wheel tire filled with an elastic mass. Widely used in military equipment in the first half of the 20th century, now gummatics are practically out of use and are used to a limited extent only on some special (construction, etc.) machines.

Ship armor is a protective layer that has a sufficiently high strength and is designed to protect parts of the ship from the effects of enemy weapons.

Krupp cemented armor (K.C.A.) is a variant of the further development of Krupp armor. The manufacturing process is largely the same with slight changes in the composition of the alloy: 0.35% carbon, 3.9% nickel, 2.0% chromium, 0.35% manganese, 0.07% silicon, 0.025% phosphorus, 0.020% sulfur . K.C.A. had the hard surface of the Krupp armor through the use of carbonaceous gases, but also had a higher "fiber" elasticity in the back of the sheet. This increased elasticity...

Bottom gas generator - a device at the rear of some artillery shells that increases their range by up to 30%.

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Active protection is a type of protection for a combat vehicle (BM), used in active mode on aircraft (LA), armored vehicles, and so on.

Tank (English tank) - an armored fighting vehicle, most often on a caterpillar track, usually with cannon armament, usually in a rotating full-turn turret, designed mainly for direct fire. and after the Second World War, experiments were carried out to create tanks with rocket weapons as the main one. Variants of tanks with flamethrower weapons are known. Definitions...

Pneumatic weapon - a type of small arms in which the projectile takes off under the influence of a gas under pressure.

An armor-piercing aerial bomb (in the USSR Air Force and the USSR Navy Air Force was abbreviated BrAB or BRAB) is a class of aerial bombs designed to destroy objects with powerful armor protection (large warships, armored coastal batteries, armored structures of long-term defensive structures (armored domes, etc.). They could also hit all those targets (except for hard-surface runways), for the destruction of which concrete-piercing aerial bombs were regularly used....

Air bomb or air bomb, one of the main types of aviation weapons (ASP). It is dropped from an airplane or other aircraft, separating from the holders under the action of gravity or with a low initial speed (with forced separation).

A high-explosive fragmentation projectile (OFS) is a main-purpose artillery ammunition that combines fragmentation and high-explosive action and is designed to hit a large number of types of targets: defeating enemy manpower in open areas or in fortifications, destroying lightly armored vehicles, destroying buildings, fortifications and fortifications, making passages in minefields, etc.

Tochka (GRAU index - 9K79, under the INF Treaty - OTR-21) - Soviet tactical missile system of the divisional level (since the late 1980s transferred to the army level) developed by the Kolomna Design Bureau of Mechanical Engineering under the leadership of Sergei Pavlovich Invincible.

An anti-tank guided missile (abbr. ATGM) is a type of guided missile munitions designed to fire from barreled artillery and tank weapons (guns or guns). Often identified with an anti-tank guided missile (ATGM), although the two terms are not synonymous.

A small-caliber high-explosive projectile is a type of ammunition filled with explosives, the damaging effect of which is achieved mainly due to the shock wave formed during the explosion. This is its fundamental difference from fragmentation ammunition, whose damaging effect on the target is associated mainly with the fragmentation field formed as a result of fragmentation of the projectile body during the detonation of an explosive charge.

Sub-caliber ammunition - ammunition, the diameter of the warhead (core) of which is less than the diameter of the barrel. Most often used to combat armored targets. The increase in armor penetration compared to conventional armor-piercing ammunition occurs due to an increase in the initial velocity of ammunition and specific pressure in the process of penetrating armor. For the manufacture of the core, materials with the highest specific gravity are used - based on tungsten, depleted uranium and others. To stabilize...

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An anti-tank grenade is an explosive or incendiary device used by infantry to fight armored vehicles using muscle power or non-artillery devices. Anti-tank mines do not formally belong to this category of weapons, however, there were universal grenade mines and anti-aircraft mines similar in design to grenades. Anti-tank missiles may be classified as "grenades", depending on the national classification of such weapons ...

Mortar-mortar (English gun-mortar) - an artillery gun of an intermediate type between a mortar and a type of artillery system, which is currently called a mortar - having a short barrel (with a barrel length less than 15 calibers), loaded from the muzzle or from the breech barrel and mounted on a massive plate (moreover, the recoil momentum is transmitted to the plate not directly from the barrel, but indirectly through the carriage design). This design type has become widespread during ...

Cumulative effect, Munroe effect - strengthening the effect of an explosion by concentrating it in a given direction, achieved by using a charge with a notch opposite the location of the detonator and facing the target. The cumulative recess is usually conical in shape, covered with a metal lining, the thickness of which can vary from fractions of a millimeter to several millimeters.

Armor-piercing bullet - a special type of bullet designed to hit lightly armored targets. Refers to the so-called special ammunition, created to expand the tactical capabilities of small arms.

All protective structures of body armor can be divided into five groups, depending on the materials used:

Textile (woven) armor based on aramid fibers

Today, ballistic fabrics based on aramid fibers are the basic material for civilian and military body armor. Ballistic fabrics are produced in many countries of the world and differ significantly not only in names, but also in characteristics. Abroad, these are Kevlar (USA) and Twaron (Europe), and in Russia - a number of aramid fibers, which differ markedly from American and European ones in their chemical properties.

What is aramid fiber? Aramid looks like thin yellow gossamer fibers (other colors are very rarely used). Aramid threads are woven from these fibers, and ballistic fabric is subsequently made from the threads. Aramid fiber has a very high mechanical strength.

Most experts in the field of body armor development believe that the potential of Russian aramid fibers has not yet been fully realized. For example, armor structures made from our aramid fibers are superior to foreign ones in terms of "protection characteristics / weight". And some composite structures in this indicator are no worse than structures made of ultra-high molecular weight polyethylene (UHMWPE). At the same time, the physical density of UHMWPE is 1.5 times less.

Ballistic fabric brands:

  • Kevlar ® (DuPont, USA)
  • Twaron ® (Teijin Aramid, Netherlands)
  • SVM, RUSAR® (Russia)
  • Heracron® (Colon, Korea)

Metal armor based on steel (titanium) and aluminum alloys

After a long break from the days of medieval armor, armor plates were made of steel and were widely used during the First and Second World Wars. Light alloys began to be used later. For example, during the war in Afghanistan, body armor with elements of armor aluminum and titanium became widespread. Modern armor alloys make it possible to reduce the thickness of panels by two to three times compared to panels made of steel, and, consequently, reduce the weight of the product by two to three times.

Aluminum armor. Aluminum outperforms steel armor, providing protection against 12.7mm or 14.5mm AP bullets. In addition, aluminum is provided with a raw material base, is more technologically advanced, welds well and has a unique anti-fragmentation and anti-mine protection.

titanium alloys. The main advantage of titanium alloys is the combination of corrosion resistance and high mechanical properties. To obtain a titanium alloy with predetermined properties, it is alloyed with chromium, aluminum, molybdenum and other elements.

Ceramic armor based on composite ceramic elements

Since the beginning of the 80s, ceramic materials have been used in the production of armored clothing, surpassing metals in terms of the "degree of protection / weight" ratio. However, the use of ceramics is only possible in combination with ballistic fiber composites. At the same time, it is necessary to solve the problem of low survivability of such armored panels. Also, it is not always possible to effectively realize all the properties of ceramics, since such an armored panel requires careful handling.

In the Russian Ministry of Defense, the task of high survivability of ceramic armor panels was identified back in the 1990s. Until then, ceramic armor panels were much inferior to steel ones in this indicator. Thanks to this approach, today the Russian troops have a reliable development - the armored panels of the Granit-4 family.

The bulk of body armor abroad consists of composite armor panels, which are made from solid ceramic monoplates. The reason for this is that for a soldier during combat operations, the chance of being repeatedly hit in the area of ​​​​the same armor panel is extremely small. Secondly, such products are much more technologically advanced; less labor-intensive, and hence their cost is much lower than the cost of a set of smaller tiles.

Used elements:

  • Aluminum oxide (corundum);
  • Boron carbide;
  • Silicon carbide.

Composite armor based on high modulus polyethylene (laminated plastic)

To date, armor panels based on UHMWPE fibers (ultra-high-modulus polyethylene) are considered the most advanced type of armored clothing from class 1 to 3 (in terms of weight).

UHMWPE fibers have high strength, catching up with aramid ones. Ballistic products made of UHMWPE have positive buoyancy and do not lose their protective properties, unlike aramid fibers. However, UHMWPE is completely unsuitable for the manufacture of body armor for the army. In military conditions, there is a high probability that the bulletproof vest will come into contact with fire or hot objects. Moreover, body armor is often used as bedding. And UHMWPE, no matter what properties it has, still remains polyethylene, the maximum operating temperature of which does not exceed 90 degrees Celsius. However, UHMWPE is excellent for making police vests.

It is worth noting that a soft armor panel made of a fibrous composite is not capable of providing protection against bullets with a carbide or heat-strengthened core. The maximum that a soft fabric structure can provide is protection from pistol bullets and shrapnel. To protect against bullets from long-barreled weapons, it is necessary to use armored panels. When exposed to a bullet from a long-barreled weapon, a high concentration of energy is created in a small area, moreover, such a bullet is a sharp striking element. Soft fabrics in bags of reasonable thickness will no longer hold them. That is why it is advisable to use UHMWPE in a design with a composite base of armored panels.

The main suppliers of UHMWPE aramid fibers for ballistic products are:

  • Dyneema® (DSM, Netherlands)
  • Spectra® (USA)

Combined (layered) armor

Materials for body armor of the combined type are selected depending on the conditions in which the body armor will be used. NIB developers combine the materials used and use them together - thus, it was possible to significantly improve the protective properties of body armor. Textile-metal, ceramic-organoplastic and other types of combined armor are widely used today throughout the world.

The level of protection of body armor varies depending on the materials used in it. However, today not only the materials for bulletproof vests themselves play a decisive role, but also special coatings. Thanks to the advances in nanotechnology, models are already being developed whose impact resistance has been increased many times over while significantly reducing thickness and weight. This possibility arises due to the application of a special gel with nano-cleaners to the hydrophobized Kevlar, which increases the resistance of Kevlar to dynamic impact by five times. Such armor can significantly reduce the size of the body armor, while maintaining the same protection class.

Read about the classification of PPE.

The use of non-metallic composite materials in the armor of combat vehicles has not been a secret for anyone for many decades. Such materials, in addition to the main steel armor, began to be widely used with the advent of a new generation of post-war tanks in the 1960s and 70s. For example, the Soviet T-64 tank had frontal hull armor with an intermediate layer of armored fiberglass (STB), and ceramic rods were used in the frontal parts of the turret. This decision significantly increased the resistance of the armored object to the effects of cumulative and armor-piercing sub-caliber projectiles.

Modern tanks are equipped with combined armor, designed to significantly reduce the impact of damaging factors of new anti-tank weapons. In particular, fiberglass and ceramic fillers are used in the combined armor of domestic T-72, T-80 and T-90 tanks, a similar ceramic material is used to protect the British Challenger main tank (Chobham armor) and the French Leclerc main tank. Composite plastics are used as lining in the habitable compartments of tanks and armored vehicles, excluding the damage to the crew by secondary fragments. Recently, armored vehicles have appeared, the body of which consists entirely of composites based on fiberglass and ceramics.

Domestic experience

The main reason for the use of non-metallic materials in armor is their relatively low weight with an increased level of strength, as well as resistance to corrosion. So, ceramics combines the properties of low density and high strength, but at the same time it is quite fragile. But polymers have both high strength and viscosity, and are convenient for shaping that is inaccessible to armor steel. It is especially worth noting fiberglass, on the basis of which experts from different countries have long been trying to create an alternative to metal armor. Such work began after World War II in the late 1940s. At that time, the possibility of creating light tanks with plastic armor was seriously considered, since it, with a smaller mass, theoretically made it possible to significantly increase ballistic protection and increase anti-cumulative resistance.

Fiberglass body for tank PT-76

In the USSR, experimental development of bulletproof and projectile-proof armor made of plastics began in 1957. Research and development work was carried out by a large group of organizations: VNII-100, Research Institute of Plastics, Research Institute of Fiberglass, Research Institute-571, Moscow Institute of Physics and Technology. By 1960, the VNII-100 branch developed the design of the armored hull of the PT-76 light tank using fiberglass. According to preliminary calculations, it was supposed to reduce the weight of the body of the armored object by 30% or even more, while maintaining projectile resistance at the level of steel armor of the same weight. At the same time, most of the mass savings were achieved due to the power structural parts of the hull, that is, the bottom, roof, stiffeners, etc. The hull mock-up, the details of which were produced at the Karbolit plant in Orekhovo-Zuyevo, passed shelling tests, as well as sea trials by towing.

Although the projected projectile resistance was confirmed, the new material did not give any advantages in other respects - the expected significant decrease in radar and thermal visibility did not occur. In addition, in terms of the technological complexity of production, the possibility of repair in the field, and technical risks, fiberglass armor was inferior to materials made of aluminum alloys, which were considered more preferable for light armored vehicles. The development of armored structures, consisting entirely of fiberglass, was soon curtailed, as the creation of combined armor for a new medium tank (later adopted by the T-64) began in full swing. Nevertheless, fiberglass began to be actively used in the civil automotive industry to create wheeled all-terrain vehicles of the ZiL brand.

So, in general, research in this area was progressing successfully, because composite materials had many unique properties. One of the important results of these works was the appearance of combined armor with a ceramic face layer and a reinforced plastic substrate. It turned out that such protection is highly resistant to armor-piercing bullets, while its mass is 2-3 times less than steel armor of similar strength. Such combined armor protection already in the 1960s began to be used on combat helicopters to protect the crew and the most vulnerable units. Later, a similar combined protection began to be used in the production of armored seats for pilots of army helicopters.

The results achieved in the Russian Federation in the field of development of non-metallic armor materials are shown in the materials published by specialists of OAO NII Stali, the largest developer and manufacturer of integrated protection systems in Russia, among them Valery Grigoryan (President, Director for Science of OAO NII Steel ”, Doctor of Technical Sciences, Professor, Academician of the Russian Academy of Sciences), Ivan Bespalov (Head of Department, Candidate of Technical Sciences), Alexey Karpov (Leading Researcher of JSC “NII Steel”, Ph.D. in Technical Sciences).

Tests of ceramic armor panels to enhance the protection of the BMD-4M

Specialists of the Research Institute of Steel write that in recent years the organization has developed class 6a protective structures with a surface density of 36-38 kilograms per square meter based on boron carbide produced by VNIIEF (Sarov) on a substrate of high molecular weight polyethylene. ONPP Tekhnologiya, with the participation of JSC Research Institute of Steel, managed to create class 6a protective structures with a surface density of 39-40 kilograms per square meter based on silicon carbide (also on a substrate of ultra-high molecular weight polyethylene - UHMWPE).

These structures have an undeniable weight advantage compared to corundum-based armor structures (46-50 kilograms per square meter) and steel armor elements, but they have two disadvantages: low survivability and high cost.

It is possible to achieve an increase in the survivability of organic-ceramic armor elements up to one shot per square decimeter by making them stacked from small tiles. So far, one or two shots can be guaranteed in an armored panel with a UHMWPE substrate with an area of ​​five to seven square decimeters, but no more. It is no coincidence that foreign standards of bullet resistance require testing of an armor-piercing rifle bullet with only one shot into a protective structure. Achieving survivability up to three shots per square decimeter remains one of the main tasks that leading Russian developers are striving to solve.

High survivability can be obtained by using a discrete ceramic layer, ie a layer consisting of small cylinders. Such armor panels are manufactured, for example, by TenCate Advanced Armor and other companies. Other things being equal, they are about ten percent heavier than flat ceramic panels.

As a substrate for ceramics, pressed panels made of high molecular weight polyethylene (Dyneema or Spectra type) are used as the lightest energy-intensive material. However, it is produced only abroad. Russia should also set up its own production of fibers, and not just press panels from imported raw materials. It is also possible to use composite materials based on domestic aramid fabrics, but their weight and cost largely exceed those of polyethylene panels.

Further improvement of the characteristics of composite armor based on ceramic armor elements in relation to armored vehicles is carried out in the following main areas.

Improving the quality of armored ceramics. For the last two or three years, the Research Institute of Steel has been closely cooperating with manufacturers of armored ceramics in Russia - NEVZ-Soyuz OJSC, Alox CJSC, Virial LLC in terms of testing and improving the quality of armored ceramics. By joint efforts, it was possible to significantly improve its quality and practically bring it to the level of Western samples.

Development of rational design solutions. A set of ceramic tiles has special zones near their joints, which have reduced ballistic characteristics. In order to equalize the properties of the panel, a design of a "profiled" armor plate has been developed. These panels are installed on the car "Punisher" and have successfully passed preliminary tests. In addition, structures based on corundum with a substrate of UHMWPE and aramids with a weight of 45 kilogram-force per square meter were tested for a class 6a panel. However, the use of such panels in AT and BTVT objects is limited due to additional requirements (for example, resistance to side detonation of an explosive device).

Shell-tested cockpit protected by combined armor with ceramic tiles

For armored vehicles such as infantry fighting vehicles and armored personnel carriers, an increased fire effect is characteristic, so that the maximum density of lesions that a ceramic panel assembled according to the “solid armor” principle can provide may be insufficient. The solution to this problem is possible only when using discrete ceramic assemblies of hexagonal or cylindrical elements, commensurate with the means of destruction. The discrete layout ensures maximum survivability of the composite armor panel, the ultimate damage density of which is close to that of metal armor structures.

However, the weight characteristics of discrete ceramic armor compositions with a base in the form of an aluminum or steel armor plate are five to ten percent higher than those of solid ceramic panels. The advantage of panels made of discrete ceramics is that they do not need to be glued to the substrate. These armor panels were installed and tested on prototypes of the BRDM-3 and BMD-4. Currently, such panels are used as part of the Typhoon and Boomerang R&D projects.

Foreign experience

In 1965, specialists from the American company DuPont created a material called Kevlar. It was an aramid synthetic fiber, which, according to the developers, is five times stronger than steel for the same mass, but at the same time has the flexibility of a conventional fiber. Kevlar has become widely used as an armor material in aviation and in the creation of personal protective equipment (body armor, helmets, etc.). In addition, Kevlar began to be introduced into the protection system of tanks and other armored combat vehicles as a lining to protect against secondary damage to the crew by armor fragments. Later, a similar material was created in the USSR, however, it was not used in armored vehicles.

American experimental BBM CAV with fiberglass hull

In the meantime, more advanced cumulative and kinetic weapons appeared, and with them the requirements for armor protection of equipment grew, which increased its weight. Reducing the mass of military equipment without compromising protection was almost impossible. But in the 1980s, the development of technology and the latest developments in the chemical industry made it possible to return to the idea of ​​​​fiberglass armor. For example, the American company FMC, engaged in the production of military vehicles, created a prototype turret for the M2 Bradley infantry fighting vehicle, the protection of which was a single piece of fiberglass reinforced composite (with the exception of the frontal part). In 1989, tests began on the Bradley BMP with an armored hull, which included two upper parts and a bottom made of multilayer composite plates, and a lightweight chassis frame was made of aluminum. According to the test results, it was found that in terms of the level of ballistic protection, this vehicle corresponds to the standard BMP M2A1 with a decrease in body weight by 27%.

Since 1994, in the United States, as part of the Advanced Technology Demonstrator (ATD) program, a prototype of an armored combat vehicle called the CAV (Composite Armored Vehicle) has been created. Its hull was to consist entirely of combined armor based on ceramics and fiberglass using the latest technologies, due to which it was planned to reduce the total mass by 33% at a level of protection equivalent to armored steel, and, accordingly, increase mobility. The main purpose of the CAV machine, the development of which was entrusted to United Defense, was a clear demonstration of the possibility of using composite materials in the manufacture of armored hulls for promising infantry fighting vehicles, armored personnel carriers and other combat vehicles.

In 1998, a prototype CAV tracked vehicle weighing 19.6 tons was demonstrated. The hull was made of two layers of composite materials: the outer one was made of ceramic based on aluminum oxide, the inner one was made of fiberglass reinforced with high-strength glass fiber. In addition, the inner surface of the hull had an anti-fragmentation lining. The fiberglass bottom, in order to increase protection against mine explosions, had a structure with a honeycomb base. The undercarriage of the car was covered with side screens made of a two-layer composite. To accommodate the crew in the bow, an isolated fighting compartment was provided, made by welding from titanium sheets and having additional armor made of ceramics (forehead) and fiberglass (roof) and anti-fragmentation lining. The car was equipped with a 550 hp diesel engine. and hydromechanical transmission, its speed reached 64 km / h, the cruising range was 480 km. As the main armament on the hull, a rising platform of circular rotation with a 25-mm M242 Bushmaster automatic cannon was installed.

Tests of the prototype CAV included studies of the hull's ability to withstand shock loads (it was even planned to install a 105-mm tank gun and conduct a series of firings) and sea trials with a total mileage of several thousand kilometers. In total, up to 2002, the program provided for spending up to 12 million dollars. But the work never left the experimental stage, although it clearly demonstrated the possibility of using composites instead of classic armor. Therefore, developments in this direction were continued in the field of improving the technologies for creating heavy-duty plastics.

Germany also did not stay away from the general trend, and since the end of the 1980s. conducted active research in the field of non-metallic armored materials. In 1994, Mexas bulletproof and projectile-proof composite armor developed by IBD Deisenroth Engineering based on ceramics was accepted for supply in this country. It has a modular design and is used as an additional hinged protection for armored combat vehicles, mounted on top of the main armor. According to the company representatives, Mexas composite armor effectively protects against armor-piercing ammunition with a caliber of up to 14.5 mm. Subsequently, Mexas armor modules began to be widely used to increase the security of main tanks and other combat vehicles from different countries, including the Leopard-2 tank, ASCOD and CV9035 infantry fighting vehicles, Stryker, Piranha-IV armored personnel carriers, Dingo and Fennec armored vehicles. ", as well as a self-propelled artillery installation PzH 2000.

At the same time, since 1993, work has been going on in the UK to create a prototype ACAVP (Advanced Composite Armored Vehicle Platform) machine with a body made entirely of fiberglass-based composite and fiberglass-reinforced plastic. Under the general guidance of the DERA (Defence Evaluation and Research Agency) of the Ministry of Defense, specialists from Qinetiq, Vickers Defense Systems, Vosper Thornycroft, Short Brothers and other contractors created a composite monocoque hull as part of a single development work. The aim of the development was to create a prototype tracked armored fighting vehicle with protection similar to metal armor, but with a significantly reduced weight. First of all, this was dictated by the need to have full-fledged military equipment for the rapid reaction forces, which could be transported by the most massive C-130 Hercules military transport aircraft. In addition to this, the new technology made it possible to reduce the noise of the machine, its thermal and radar visibility, extend the service life due to high corrosion resistance and, in the future, reduce the cost of production. To speed up the work, components and assemblies of the serial British BMP Warrior were used.

British experienced AFV ACAVP with fiberglass hull

By 1999, Vickers Defense Systems, which carried out the design work and the overall integration of all prototype subsystems, submitted the ACAVP prototype for testing. The mass of the car was about 24 tons, the 550 hp engine, combined with a hydromechanical transmission and an improved cooling system, allows you to reach speeds of up to 70 km / h on the highway and 40 km / h on rough terrain. The vehicle is armed with a 30mm automatic cannon paired with a 7.62mm machine gun. In this case, a standard turret from the serial Fox BRM with metal armor was used.

In 2001, the ACAVP tests were successfully completed and, according to the developer, demonstrated impressive security and mobility indicators (it was ambitiously stated in the press that the British allegedly created a composite armored vehicle “for the first time in the world”). The composite hull provides guaranteed protection against armor-piercing bullets of up to 14.5 mm caliber in the lateral projection and from 30 mm projectiles in the frontal projection, and the material itself eliminates secondary damage to the crew by fragments when the armor is pierced. Additional modular armor is also provided to enhance protection, which is mounted on top of the main armor and can be quickly dismantled when transporting the vehicle by air. In total, the car passed 1800 km during testing and no serious damage was recorded, and the hull successfully withstood all shock and dynamic loads. In addition, it was reported that the weight of the machine is 24 tons - this is not the final result, this figure can be reduced by installing a more compact power unit and hydropneumatic suspension, and the use of lightweight rubber tracks can seriously reduce the noise level.

Despite the positive results, the ACAVP prototype turned out to be unclaimed, although the DERA management planned to continue research until 2005, and subsequently create a promising BRM with composite armor and a crew of two. Ultimately, the program was curtailed, and further design of a promising reconnaissance vehicle was already carried out according to the TRACER project using proven aluminum alloys and steel.

Nevertheless, work on the study of non-metallic armor materials for equipment and personal protection was continued. In some countries, their own analogues of the Kevlar material have appeared, such as Twaron by the Danish company Teijin Aramid. It is a very strong and lightweight para-aramid fiber, which is supposed to be used in the armor of military equipment and, according to the manufacturer, can reduce the total weight of the structure by 30-60% compared to traditional counterparts. Another material, called "Dynema", manufactured by DSM Dyneema is a high-strength ultra-high molecular weight polyethylene (UHMWPE) fiber. According to the manufacturer, UHMWPE is the most durable material in the world - 15 times stronger than steel (!) And 40% stronger than aramid fiber of the same mass. It is planned to be used for the production of body armor, helmets and as armor for light combat vehicles.

Light armored vehicles made of plastic

Taking into account the accumulated experience, foreign experts concluded that the development of promising tanks and armored personnel carriers fully equipped with plastic armor is still a rather controversial and risky business. But new materials turned out to be in demand in the development of lighter wheeled vehicles based on production cars. So, from December 2008 to May 2009 in the United States at the Nevada test site, a light armored car with a hull made entirely of composite materials was tested. The vehicle, designated ACMV (All Composite Military Vehicle), developed by TPI Composites, successfully passed life and sea trials, driving a total of 8,000 kilometers on asphalt and dirt roads, as well as cross-country. Fire and demolition tests were planned. The base of the experimental armored car was the famous HMMWV - "Hammer". When creating all the structures of its body (including frame beams), only composite materials were used. Due to this, TPI Composites managed to significantly reduce the weight of the ACMV and, accordingly, increase its carrying capacity. In addition, it is planned to extend the service life of the machine by an order of magnitude due to the expected greater durability of composites compared to metal.

Significant progress in the use of composites for light armored vehicles has been made in the UK. In 2007, at the 3rd International Exhibition of Defense Systems and Equipment in London, a Cav-Cat armored car based on an Iveco medium-duty truck equipped with NP Aerospace's CAMAC composite armor was demonstrated. In addition to standard armor, additional protection was provided for the sides of the vehicle through the installation of modular armor panels and anti-cumulative grilles, also consisting of a composite. An integrated approach to the protection of CavCat made it possible to significantly reduce the impact on the crew and landing force of explosions of mines, shrapnel and light infantry anti-tank weapons.

American experienced ACMV armored car with a fiberglass hull

British CfvCat armored vehicle with additional anti-cumulative screens

It is worth noting that earlier NP Aerospace has already demonstrated CAMAS armor on the Landrover Snatch light armored car as part of the Cav100 armor set. Now similar kits Cav200 and Cav300 are offered for medium and heavy wheeled vehicles. Initially, the new armor material was created as an alternative to metal composite bulletproof armor with a high protection class and overall structural strength at a relatively low weight. It was based on a pressed multilayer composite, which allows forming a solid surface and creating a case with a minimum of joints. According to the manufacturer, the CAMAC armor material provides a modular "monocoque" design with optimal ballistic protection and the ability to withstand strong structural loads.

But NP Aerospace has gone further and now offers to equip light combat vehicles with new dynamic and ballistic composite protection of its own production, expanding its version of the protection complex by creating EFPA and ACBA attachments. The first is plastic blocks stuffed with explosives, installed on top of the main armor, and the second is cast composite armor blocks, also additionally installed on the hull.

Thus, light wheeled armored fighting vehicles with composite armor protection, developed for the army, no longer looked like something out of the ordinary. A symbolic milestone was the victory of the industrial group Force Protection Europe Ltd in September 2010 in a tender for the supply to the British armed forces of a light armored patrol vehicle LPPV (Light Protected Patrol Vehicle), called Ocelot. The British Ministry of Defense decided to replace the outdated Land Rover Snatch army vehicles, as they did not justify themselves in modern combat conditions in Afghanistan and Iraq, with a promising vehicle with armor made of non-metallic materials. As partners of Force Protection Europe, which has extensive experience in the production of highly protected vehicles such as MRAP, the automaker Ricardo plc and KinetiK, which deals with armor, were chosen.

Ocelot has been under development since the end of 2008. The designers of the armored car decided to create a fundamentally new vehicle based on the original design solution in the form of a universal modular platform, unlike other samples that are based on serial commercial chassis. In addition to the V-shaped bottom of the hull, which increases protection against mines by dissipating the energy of the explosion, a special suspended armored box-shaped frame called the "skateboard" was developed, inside which the driveshaft, gearbox and differentials were placed. The new technical solution made it possible to redistribute the weight of the machine in such a way that the center of gravity was as close to the ground as possible. Wheel suspension - torsion bar with a large vertical travel, drives to all four wheels - separate, nodes of the front and rear axles, as well as wheels - are interchangeable. The hinged cab, in which the crew is located, is hinged to the “skateboard”, which allows the cab to be tilted to the side for access to the transmission. Inside there are seats for two crew members and four paratroopers. The latter sit facing each other, their seats are fenced off by pylon partitions, which additionally reinforce the hull structure. To access the inside of the cab, there are doors on the left side and in the rear, as well as two hatches in the roof. Additional space is provided for the installation of various equipment, depending on the intended purpose of the machine. A Steyr diesel auxiliary power unit is installed to power the instruments.

The first prototype of the Ocelot machine was made in 2009. Its mass was 7.5 tons, the payload mass was 2 tons, the maximum speed on the highway was 110 km / h, the cruising range was 600 km, the turning radius was about 12 m. 40°, wading depth up to 0.8 m. Low center of gravity and wide base between the wheels ensures rollover stability. Cross-country ability is increased by using larger 20-inch wheels. Most of the suspended cabin consists of armored figured composite armor panels reinforced with fiberglass. There are mounts for an additional set of body armor. The design provides rubberized areas for mounting units, which allows to reduce noise, vibration and increase the insulation strength compared to a conventional chassis. According to the developers, the basic design provides protection for the crew from explosions and firearms above the level of the STANAG IIB standard. It is also claimed that a complete replacement of the engine and gearbox can be done in the field within one hour using only standard tools.

The first deliveries of Ocelot armored vehicles began at the end of 2011, and by the end of 2012, about 200 of these vehicles had entered the British armed forces. Force Protection Europe, in addition to the basic LPPV patrol model, has also developed options with a WMIK (Weapon Mounted Installation Kit) weapon module with a crew of four and a cargo version with a cabin for 2 people. She is currently participating in the Australian Department of Defense tender for the supply of armored vehicles.

So, the creation of new non-metallic armor materials in recent years is in full swing. Perhaps the time is not far off when armored vehicles adopted for service, which do not have a single metal part in their body, will become commonplace. Light but durable armor protection is of particular relevance now, when low-intensity armed conflicts flare up in different parts of the world, numerous anti-terrorist and peacekeeping operations are being carried out.