RU147175U1 - DISTINCTED Bronestructure - Google Patents

Abstract

1. Diversity armored structure for protection against armor-piercing bullets with a high hard core, consisting of the first and second sheets of the crushing layer installed with a gap to each other, and the sheet of the trapping layer, the sheets of the crushing layer are made of low alloy armored steel with a low tempered martensite structure, characterized in that the sheet of the capture layer is set with a gap to the crushing layer, and it is made of low alloy armored steel with a structure of low tempered martensite. 2. An exploded bulletproof structure according to claim 1, characterized in that the first and second sheet of the crushing layer are located at an angle to each other. An exploded bulletproof structure according to claims 1 and 2, characterized in that the gaps are filled with foamed filler of a polymer or metal. 4. The spaced armored structure according to claim 3, characterized in that the foamed filler has a closed porosity.

Description

The utility model relates to armored structures, namely to means of protection against the effects of armor-piercing bullets of small arms, and can be used when booking objects for various purposes, including the manufacture of armored vehicles and swimming vehicles.

A known design bulletproof heterogeneous steel armor (see RU 2472100, 01/10/2013, F41H 5/04), consisting of two layers of steel, rigidly interconnected, and the material of the front layer is hardened and has a hardness of HRc 62 ÷ 65, and the back - not heat-treated and has an elastic modulus (1.9 -: - 2.1) × 10 ¹¹ Pa. However, serial armor steel, which allows HRc 62–65 to be achieved during hardening, is not produced in Russia; moreover, the adhesive bonding of layers provided for in this technical solution cannot provide sufficient survivability of the barrier under ballistic conditions.

The composite armor construction is also known (see RU 2329455, 07/20/2008, F41H 5/04), consisting of a crushing-deflecting layer of ceramic elements and a metal retaining layer, rigidly bonded to each other using a compound through an elastic-plastic gasket. The disadvantages of this technical solution include the high cost and not the manufacturability of ceramic armor, as well as the low efficiency of its "work" against bullets with carbide tungsten cores.

Closest to the proposed solution is the spaced armored structure implemented in the reservation scheme for the middle frontal part of the BMP 3 (see OA Gomyrin, A.Ya. Shumilov “Features of the hull and turrets of the BMP 3”, “Bulletin of Armored vehicles”, No. 5, 1991,). In it, in front of the main (catching) armored barrier, a crushing layer of two 10 mm sheets of serial “77” armored steel sheets with a gap of 70 mm is installed, and the catching layer is made of ABT102 armored aluminum plate with a thickness of 60 mm (BMP body). This structure allows you to effectively fragment highly hard armor-piercing cores on the crushing assembly, and stop the flow of fragments formed on the main armor. This structure in the modern classification provides protection class 6 according to the OTT standard 9.1.12-1-2010, which provides for non-penetration of armor by B32 bullets of 14.5 mm caliber and 12.7 mm BS caliber.

However, its weight in steel equivalent is about 42 mm, but a homogeneous plate of medium-hardness armored steel with a thickness of 40 mm provides the same level of bulletproof protection, i.e. compared to a homogeneous sheet of armored steel, this design does not provide any gain in weight, and the use of a monolithic armored barrier with the same protection characteristics is always preferable. Moreover, the use of non-ferrous metals in the design of armor complicates the technology of its manufacture and leads to a noticeable rise in the cost of the structure.

The objective of the claimed solution is to develop a spaced armored structure for protection against armor-piercing bullets, which would eliminate the disadvantages of the prototype and provide the required class of protection.

The technical result of the utility model is to reduce the weight of the spaced armored structure as compared to a homogeneous sheet providing the same level of bulletproof protection, as well as simplifying and cheapening its manufacturing technology.

To achieve this result, an exploded armored structure is proposed for protection against armor-piercing bullets with a high hard core, consisting of two sheets of a crushing layer installed with a gap to each other, and a sheet of a trapping layer, while a sheet of a trapping layer is installed with a gap to the second sheet of a crushing layer, and the sheets in the layers are standard sheets of serial domestic low-alloy armored steel with the structure of low tempered martensite.

The installation of a structural gap between the crushing and trapping layers in the design of the prototype allows the formation of a cone of dissipation of the energy of fragments generated after the core passes through the bullet of the crushing layer, which reduces the load on the sheet of the trapping layer due to the distribution of the energy of the fragmentation stream over its surface and thereby reduces weight of spaced armored structure without lowering the level of bulletproof protection, providing a gain in weight compared to a monolithic armor Rada, providing the same level of bulletproof protection. And the use of only standard sheets of serial low-alloyed armored steel with the structure of low-tempered martensite in the proposed spaced armored structure simplifies the technology of its manufacture, since this steel is the cheapest, most technologically advanced and most effective, and, therefore, the most demanded material.

To further lighten the weight of the structure, it is proposed that in the proposed spaced armored structure, the sheets in the crushing layer be installed at an angle to each other. This design allows you to reduce the thickness of the sheets in the crushing layer while maintaining guaranteed destruction of the bullet core when passing through this layer due to the misalignment of its interaction with the barrier. However, the use of such a design of the crushing layer in an armored structure with a high degree of bulletproof protection (for example, against 12.7 mm caliber armor-piercing bullets) is not practical, since the mass of the armor increases and its design is complicated.

The thickness of the sheets of each layer and the gaps between them are selected depending on the requirements for bulletproof protection for the armored structure.

Currently, there are various types of armor-piercing bullets in service, which differ from each other both in caliber and in the material of the core used in them. Depending on the type of bullets, and more precisely on the degree of their impact, systems have been developed that classify armored objects into classes depending on their degree of protection. The main systems are the domestic classification of personal protective equipment (PPE) according to GOST RV15.307 / GOST R50744-95 and mobile armored objects according to OTT 9.1.12-1-2010, as well as the international system STANAG 4569. Classifications according to OTT 9.1.12-1- 2010 and STANAG 4569 overlap in many respects, but there are also differences associated with taking into account or ignoring certain weapons.

Domestic armored steel, as a rule, is produced in standard thicknesses, tied to certain levels of protection of PPE in accordance with GOST RV15.307 / GOST R50744-95 and prescribed in the relevant standards (GOST and TU), therefore it is possible to work when booking objects only with discrete set of thicknesses of standard armor plates of steels of various grades.

Various options for the implementation of armored structures on the basis of the proposed technical solution are proposed, which provide protection in accordance with the requirements of different classes of domestic (OTT 9.1.12-1-2010) and international (STANAG 4569) classifications.

The figure 1 presents the options for the proposed spaced armored structure: a) with a parallel arrangement of sheets in layers, b) a scheme with the disorientation of the sheets in the crushing layer at an angle γ.

The figure 2 presents a photo of fragmented cores of armor-piercing bullets BS caliber 12.7 mm (a) and B32 caliber 14.5 mm (b) after breaking "normal" barriers made of steel grade "AZ" with a thickness of 8.5 mm in the delivery state ( HRc 54 ÷ 58).

The figure 3 presents a photo of cracked sheets of steel "A3" with a thickness of 6.5 mm in the delivery state (HRc 54 ÷ 58), used as the second sheet in the crushing layer of the proposed armored structure, fired by B32 14.5 mm caliber bullets (a) and BS caliber 12.7 mm (b).

The figure 4 presents a photo of the cores of B32 armor-piercing bullets of 7.62 mm caliber after breaking through "44" steel barriers of the "44" grade (HRc 54 ÷ 58): actual thickness 6.5 mm (protection class GOST RV15.307 / GOST 5 P50963-96, GOST R51112-97) (a) and 4.6 mm (3rd class of protection GOST RV15.307 / GOST R50963-96, GOST R51112-97) (b).

The figure 5 presents a photo of sheets of steel "A3" with an actual thickness of 6.5 mm in the delivery state (HRc 54 ÷ 58) (protection class GOST RV15.307 / GOST R50963-96, GOST R51112-97), used as the first (b) and the second (a) sheets of the spaced armored structure with a spacing of 30 mm fired by B32 and 7N23 bullets of 7.62 mm caliber.

The figure 6 presents a photo of the cores of armor-piercing bullets B32 caliber 7.62 mm after breaking through the "spaced" barriers (crushing layer) of two standard sheets of serial armored steel grade "44" (HRc 54 ÷ 58) the actual thickness of 2.4 mm (class 2 protection GOST RV15.307 / GOST R50963-96, GOST R51112-97) of various layouts: parallel execution (a) and with an arrangement at an angle of 20 ° to each other (b).

The figure 7 presents: (a) a diagram of the bulletproof structure with misorientation of the sheets in the crushing layer; (b) ballistic analysis of weakened zones; (c) assembly and detailing diagram of an armored panel mock-up - an example of a concrete implementation of the proposed spaced armored structure for protection according to class 4 of OTT 9.1.12-1-2010 (class 3 STANAG 4569).

The spaced armored structure (see Fig. 1) consists of a crushing layer made of two sheets (1, 2) with a gap d between them, and a trapping layer in the form of one sheet (3) installed with a gap L to the second sheet (2 ) crushing layer, the sheets in the layers are made of low alloy armored steel with a structure of low tempered martensite. In another embodiment of the proposed armored structure, the sheets in the crushing layer can be installed at an angle γ to each other.

In special cases, the implementation of the proposed spaced armored structure, the gaps d and L between the sheets can be filled with foamed filler in the form of a polymer or metal. And to ensure increased buoyancy, the foamed filler is selected with closed porosity.

According to class 6 of OTT 9.1.12-1-2010, the armored structure must protect 14.5 mm caliber B32 (heat-treated steel core) and 12.7 mm caliber carbide-tungsten bullets from shelling from a distance of 100 m from armor-piercing bullets. When booking vehicles, the possibility of defeating the object’s protective structures with kinetic armor-piercing means “normal” to its surface, as the most dangerous type of exposure, is usually taken into account. Although the muzzle energy of these two bullets differs by half, and the impulse - by one and a half times, their efficiency “normal” for homogeneous steel and aluminum armor is almost the same: - 30 mm and 80 mm, respectively. Consequently, homogeneous armor that protects against the considered armor-piercing weapons will be a plate of armored steel of medium hardness with a thickness of at least 40 mm or a plate of aluminum alloy ABT102 with a thickness of at least 100 mm.

It has been experimentally established that the most optimal combination of thicknesses of the layers of the proposed armored structure (see Fig. 1a) is 8-6-6 mm of standard sheets of domestic serial armored steel installed as crushing and trapping layers. In FIG. Figure 2 shows photographs illustrating the fragmentation of both types of cores on an A3 steel barrier with an actual thickness of 8.5 mm in the delivery state (54 ÷ 58 HRc). It can be seen that the degree of destruction is quite large in the head part of the core, however, its tail part is destroyed into larger fragments, which carry the main danger to the capture layer.

The optimal gaps between the layers are defined as d = 40 mm and L = 60 mm, and the hardness of the steel in sheet 1 is 54 ÷ 58 HRc, sheet 2 is 48 ÷ 52 HRc and sheet 3 is 54 ÷ 58 HRc. The hardness value 54 ÷ 58 HRc is characteristic of standard sheets of modern domestic low-alloy armored steel for bulletproof protection with a structure of low tempered martensite, such as “77”, “44”, “A3”, “56”, “Ts-85”, etc. The reduced hardness in sheet 2 is due to the significant intensity of exposure to the primary fragmentation fragments of the core formed after passing through sheet 1, i.e. steel on sheet 2 should have increased ductility so as not to split (see Fig. 3) and provide the necessary survivability of the armor in subsequent lesions.

The proposed bulletproof structure works as follows: after primary crushing on sheet 1 (see Fig. 2), core fragments continue to move with some “expansion” both across the trajectory (formation of a dissipation cone) and along it, realizing the tensile energy released during the destruction. As can be seen from FIG. 2, in the head part of this stream, there are mainly small fragments that can be completely stopped by the subsequent block 2 so that the large back fragment (core shank) interacts not only with the second “thin” block 2, but also with those stopped on it primary fragments of the core itself. It should be borne in mind that crushing and scattering is more effective, the higher the hardness and density of the barrier elements, and the above parameters for the material of armor-piercing cores (steel U12A; VK8) significantly exceed those for armor steels. Thus, the secondary fragmentation on the second (scattering) sheet 2 of the crushing layer occurs more intensively due to small core fragments stopped on it, and the energy dissipation cone (angle of expansion of the fragments) after the second obstacle can be significantly opened due to the presence of a gap L and thus reduce the impact to the main catching barrier 3.

Attempts to change the formula of the structure of the armored composition from 8-6-6 to 6-8-6 and 6-6-8 lead only to a decrease in its durability and survivability. The investigated range of possible thicknesses of the armored barrier within a reasonable range (for moving armored objects) of up to 200 mm showed the impossibility of reducing its weight due to the use of thinner sheets of armor steel in the layers 6-6-6, 6-4 (5) -8 and 8-5 (4) -6. However, an increase in the total thickness of the barrier due to an increase in the gaps leads to a noticeable increase in its survivability: the larger the gaps between the layers, the weaker the effect on the capture layer, so with a further increase in the permissible total thickness of the armor, this approach is quite possible to implement. The possibility of reducing the weight of the armored composition in the event of impossibility of defeating it “to normal” has been investigated: it has been established that at angles of meeting of the bullet to the armor of more than 20 °, the use of scheme 6-6-6 is possible, with more significant deviations from the most critical interaction (in “normal” ), it is possible to use even thinner sheets.

The following standard sheets of domestic serial low-alloy armored steel were tested as elements of the proposed armored composition:

- sheet 1 of the crushing layer — a sheet of steel “77” of an actual thickness of 8.6 mm in the delivery state (54 ÷ 58 HRc), as well as a sheet of steel “A3” of an actual thickness of 8.5 mm in the delivery state (54 ÷ 58 HRc);

- crushing layer sheet 2 — steel sheet “1” of actual thickness 6.4 mm in the delivery state (47 ÷ 52 HRc), as well as steel sheet “AZ” of actual thickness 6.5 mm in the delivery state + “low” tempering t = 230 ° C, 2 hours, cooling with an oven (49 ÷ 51 HRc);

- sheet 3 of the capture layer - steel sheet “44” of the actual thickness of 6.6 mm with heat treatment: quenching with t = 970 ° C in oil + tempering t = 200 ° C for 3 hours (54 ÷ 58 HRc), as well as a sheet of steel “ A3 "of the actual thickness of 6.5 mm in the delivery state (54 ÷ 58 HRc) (protection class 5 according to GOST RV15.307 / GOST R50744-95).

In all considered combinations, the gaps were set d = 40 mm and L = 60 mm. All investigated combinations for both means of defeat “worked out” approximately the same way, with an estimate of the ultimate density of lesions of up to 180 m ^-2 and the probability of substandard lesions of less than 2%.

The possibility of replacing the steel sheet 3 of the capture layer with a standard ABT101 armored aluminum plate with an actual thickness of 19 mm was investigated, but the second defeat of the tested armored composition turned out to be substandard.

A decrease in both gaps (d and L) by 5 mm leads to a decrease in the survivability of the structure to a limiting density of lesions of less than 160 m ^-2 with a probability of substandard lesions = 3 ÷ 4%.

And in order to increase operational characteristics to the maximum density of damage of at least 200 m ^-2 , with the probability of substandard lesions of less than 1%, it is necessary to increase the gaps: d by 20 mm and L by 50 mm, respectively, bringing the total thickness of the armor to almost 200 mm.

Thus, the optimal armor structure for protection against armor-piercing bullets B32 caliber 14.5 mm and BS caliber 12.7 mm is a composition of three sheets of armored steel with a thickness of 1 - 8.2 ÷ 8.7 mm, 2 - 6.2 ÷ 6 , 8 mm and 3 - 6.2 ÷ 6.8 mm and with minimum gaps between them d = 40 mm and L = 60 mm (see Fig. 1), while the hardness of the first 1 and last 3 sheets is 54 ÷ 58 HRc, and the second 1 - 47 ÷ 52 HRc. Hereinafter, ranges of thicknesses of armor plates that correspond to standard ranges of thicknesses of armor plates produced in series are indicated.

It should be noted that the proposed armored structure will obviously meet the requirements of the international classification of armor protection STANAG 4569, since tests in the fourth level of this system are conducted from a distance of 200 m and bullets with a carbide tungsten core are not provided for in this class. This armored structure also protects against all armor-piercing bullets of a "lower rank": B32 of 12.7 mm caliber and from all armor-piercing weapons of small arms.

According to class 5 of the OTT 9.1.12-1-2010, the armored structure must protect against armor-piercing bullets B32 12.7 mm caliber when fired “into normal” from a distance of 100 m

It was experimentally established that the most optimal combination of thicknesses of the layers of the proposed armored structure (see Fig. 1a) is 4-6-6 mm of standard sheets of armor steel, installed as crushing and trapping layers. It was found that the core of the bullet in question does not collapse on a separate 4 mm sheet of armored steel, but when overcoming composition 4-6 with a gap of at least 18 mm, the degree of fragmentation and the opening angle of the energy dissipation cone are sufficient to hold the fragments with sheet 3 of serial low-alloy armored steel with a structure of low tempered martensite with a nominal thickness of 6 mm.

Obviously, the core destruction mechanism here is somewhat different from the previously considered: if in the previous case the primary destruction occurs due to tensile stresses in the inverted compression wave, which is created in the core in the process of breaking through the first obstacle, then in the considered case as a result of interference of two compression waves : twice inverted wave from the first obstacle (1) and the primary wave from the second obstacle (2).

The hardness requirements for armor steel in each of the layers of the considered armor composition are 54 ÷ 58 HRc, that is, standard sheets of serial modern armored bulletproof steel are used. The mechanisms implemented when the bullet is being held by the considered armored structure does not require the use of material with increased ductility in the second obstacle (2).

Thus, the optimal armored structure for protection against armor-piercing bullets B32 12.7 mm caliber is a composition of three sheets of armor steel with a thickness of 1 - 4.2 ÷ 4.7 mm, 2 - 6.2 ÷ 6.8 mm and 3 - 6 , 2 ÷ 6.8 mm and with minimum gaps between them d = 18 mm and L = 50 mm, while the hardness of each sheet is 54 ÷ 58 HRc.

This bulletproof structure also protects against all armor-piercing means of rifle calibers.

According to class 4 of OTT 9.1.12-1-2010, the armor structure must protect against armor-piercing bullets of B32 of 7.62 mm caliber from a distance of 10 m “normal” to the surface, as well as from all armor-piercing bullets of “lower rank”. In the third class, STANAG 4569, all these tools were added another M993 bullet of 7.62 mm caliber with a tungsten carbide core.

It is possible to realize a spaced armored structure that protects against B32 bullets of 7.62 mm caliber and has 15 + 20% less weight than a homogeneous sheet of serial low-alloy armored steel, for bulletproof protection with a structure of low tempered martensite, providing OTT protection class 4 9.1.12- 1-2010.

This spaced structure is an armored panel of 6-6 mm layout, consisting of two sheets of serial low-alloy armored steel with a nominal thickness of 6 mm with a gap between them. The physical basis of the "work" of this structure is the guaranteed destruction of the core of the B32 bullet of 7.62 mm caliber on the first barrier (see Fig. 4a), while sheets of armored steel of lesser thickness do not provide this effect (see Fig. 4b). As can be seen from photo 4a, core destruction occurs in a tensile wave (the destruction surface is perpendicular to the axis of the bullet). Such a wave is formed in the core upon reflection of the primary elastic compression wave generated by the interaction of the bullet with the first obstacle from the “free” back surface. As is known, the strength of solid materials under tensile conditions is significantly lower than their strength under compression conditions, thus, when a 6 mm piercing sheet is pierced, the possibility of fragmentation of the core of a B32 bullet of 7.62 mm caliber is realized. A second barrier captures these fragments. The amplitude of the primary elastic wave generated in the core upon breaking through a thinner barrier is insufficient to destroy it (see Fig. 4b).

However, tests have shown that the means of destruction of a "lower" class are able to penetrate this armored structure. Figure 5 shows a photograph of sheets of "A3" steel with a thickness of 6.5 mm, tested by B32 bullets of 7.62 mm caliber (lesions 1 ÷ 26) and 7N23 bullets of the same caliber (lesions 1 ÷ 6). It can be seen from the figure that a less energetic bullet in some cases (lesions 3 and 6 — penetration, 5 — through crack) can hit an armored panel that easily holds a more “powerful” bullet, although the material and diameter of the cores are almost the same. Only the length of the core is different. The parameters of the compression waves generated with a similar interaction geometry should be similar, therefore, it can be assumed that fracture in the tensile wave does not occur in the shorter core since the “tail” of the primary compression wave “presses” the opposing tensile wave generated by reflection of its head front from the back end of the core, not allowing destruction to occur.

Thus, in order to guarantee protection against all means of destruction stipulated by the standard in the class under consideration, it is necessary to increase the thickness of one of the layers of the structure, which is pointless since it does not give a weight gain in comparison with homogeneous armor.

Since it is not possible to guarantee the destruction of the small-caliber armor-piercing steel core of the bullet by the mechanism implemented in the first of the previously considered armored structures (in an inverted wave), the possibility of implementing a mechanism working in the second type of the previously considered armored structures (due to interference of compression waves) was investigated.

Since the core of the B32 bullet of 7.62 mm caliber does not collapse on a 4 mm steel barrier (see Fig. 4b), it simply “does not see” a two-millimeter one. However, two sheets of armored steel of the "44" grade with an actual thickness = 2.4 mm, installed with a gap of 10 mm, lead to its substantial destruction (see Fig. 6a). Comparing photos 4a and 6a, it is clear that the mechanisms of core destruction on a 6-mm barrier and the assembly of two 2-mm sheets are significantly different: if in the first case the plane of the fracture surface is strictly perpendicular to the axis of the bullet (the plane of maximum compressive / tensile stresses), which is typical for fracture in the tensile wave, then in the second case there are significant sections parallel to the maximum shear loads (45 ° to the axis of loading), which is typical for fracture in the compression wave.

Thus, the real possibility of destruction of the steel cores of armor-piercing bullets of small arms on thin spaced barriers was demonstrated. In addition, it should be noted that fracture in the compression wave leads to a significant disorientation of the formed fragments (slipping along the cleavage planes of 45 ° to the loading axis creates overturning forces leading the fragments away from the initial trajectory). In this case, it is possible to stop the resulting fragments using a thinner sheet of armor steel - with a nominal thickness of 4 mm.

However, numerous studies have shown that only 90 ÷ 95% of the steel cores are destroyed by coaxial passage of composition 2-2, and if the core of the B32 bullet of 7.62 mm caliber comes to the trapping layer, it is not destroyed and not disoriented, it is 30% of cases pierces even an 8-mm armor plate. Guaranteed destruction of the core can be achieved only if, when breaking through the first obstacles, waves with a significant bending component are generated in it, and this is possible only in the case of an “oblique impact”.

The experiments showed that with the mutual orientation of the planes of the first two sheets of the barrier at an angle of γ> 16 °, the steel armor-piercing core is guaranteed to be destroyed, while the damage is more critical than in the case of the parallel arrangement of sheets (see Fig. 6a, b). Further neutralization of its fragments occurs on a 4-mm sheet of the capture layer.

Thus, the optimal spaced armored structure for protection against armor-piercing bullets B32 caliber 7.62 mm is a composition of three sheets of armor steel with a thickness of 1 - 2.2 ÷ 2.7 mm, 2 - 2.2 ÷ 2.7 mm and 3 - 4.2 ÷ 4.8 mm, while the planes of the first two sheets 1 and 2 are misoriented at an angle γ> 16 ° with a minimum gap between them d> 8 mm (this distance the bullet overcomes at a speed of 820 m / s in the same time, which the elastic wave reaches the back end of the core and comes back), and the minimum gap between the second and third sheets is at least L> 10 mm (this is necessary IMO for the implementation of processes of core destruction and disorientation of fragments), the hardness of all sheets is 54 ÷ 58 NKs (see Fig. 16).

An example of a specific implementation of a spaced armored structure with differently oriented sheets of a crushing layer

It is proposed to manufacture the protection, in accordance with the proposed technical solution, consisting (see Fig. 7) of a capture layer in the form of a sheet of serial low-alloy armored steel of the third protection class according to GOST RV 15.307 / GOST R50744-95 (nominal thickness 4.2 ÷ 6, 8 mm) (steel “44”, “A3”, etc.) and a crushing layer, consisting of Z-shaped lamellas from sheets of serial low-alloy armored steel of the second protection class (nominal thickness 2.2 ÷ 2.7 mm) with a different orientation angle individual shelves γ = 20 °. The lamellas are superposed one on top of another with a shift (overlap) and are rigidly fastened together (for example, by welding). The maximum gap between the sheets is selected on the basis of general ideas about the compactness of the barrier.

Figure 7b shows that the weakened zones of the armor panel are at the contact points of adjacent lamellas (gap between sheets d≤8 mm) and on the outside of the lamellas, where the condition γ> 16 ° and the angle of approach of the trajectory of the bullet fragments to the capture the layer is not enough to hold it. If in the first case the problem is eliminated by the “overlap” of the lamellas against each other, then in the second case an additional armor strip has to be welded to strengthen the structure.

In FIG. 7c shows the details and assembly diagram of the armored panel. The prototype was made in the size of 740 × 400 mm and was tested with various armor-piercing means. The results are summarized in table 1. It can be seen from the table that only one impact produced an unsatisfactory lesion (No. 17) - a through crack from the rear of the capture layer without breaking through, and even then - due to being too close to defeat No. 5 (according to the standard TK for OCD according to the development of class 6a armored objects, the distance between adjacent lesions is not less than 35 mm).

The calculation of the total weight of the armored panel, taking into account the disorientation angles, "overlaps" and reinforcement, gave the surface density of the presented armored structure - 79 kg / m (10.1 mm in the "steel equivalent"). This, in comparison with homogeneous armor, gives a gain in mass of 30%, which is significant, given the use of expensive elements such as non-ferrous metal, ceramics and ballistic fiber mats. The total thickness of the armored panel was 95 mm, which is quite acceptable for moving armored vehicles.

On separate mock-ups, the “operability” of the proposed technical solution against armor-piercing bullets 7N13, 7N26 cal was tested. 7.62 mm and M995 cal. 5.56 mm (carbide-tungsten core) - mock-ups, as well as PS bullets with TU C cartridge 57-H231. All tests yielded positive results. Tests of the proposed armored mock bullets M993 cal. 7.62 mm (tungsten carbide core) - the foundations of the third level of armor protection according to STANAG 4569, showed a 50% chance of substandard lesions. Replacing a 4 mm sheet of the capture layer (C) with a standard 6 mm sheet of armored serial steel (protection class GOST RV15.307 / GOST R50744-95) eliminates this effect. Thus, an experimental verification confirmed the achievement of the specified technical result.

On the other hand, studies have shown that the carbide-tungsten core (VK8) of armor-piercing bullets is the M993 cal model. 7.62 mm (base class 3 STANAG 4569) is guaranteed to collapse on a standard 2 mm sheet of armored serial steel (class 2 of protection GOST RV15.307 / GOST R50744-95), therefore a simpler, spaced structure was proposed to hold this means of destruction: 2 -2-6 with minimal spacing d = 10 mm and L = 30 mm (see Fig. 1A). It implements the same mechanisms of destruction, dispersion, and confinement as in the first of the previously considered armored compositions. However, this armored structure is somewhat heavier than the previous one when fired with B32 cal bullets. 7.62 mm gives 5 ÷ 8% of substandard lesions, that is, the requirements of class 4 of OTT 9.1.12-1-2010 are not met.

Claims (4)

1. Diversity armored structure for protection against armor-piercing bullets with a high hard core, consisting of the first and second sheets of the crushing layer installed with a gap to each other, and the sheet of the trapping layer, the sheets of the crushing layer are made of low alloy armored steel with a low tempered martensite structure, characterized in that the sheet of the capture layer is set with a gap to the crushing layer, and it is made of low alloy armored steel with a structure of low tempered martensite. 2. Diversity armored structure according to claim 1, characterized in that the first and second sheet of the crushing layer are located at an angle to each other. 3. The spaced armored structure according to claims 1 and 2, characterized in that the gaps are filled with foamed filler of a polymer or metal. 4. Diversity armored structure according to claim 3, characterized in that the foamed filler has a closed porosity.

Images