RU2810095C1 - Armour protection - Google Patents

Abstract

FIELD: means of armour protection.

SUBSTANCE: armour protection contains shaped ceramic elements fixed on a substrate and connected by their end surfaces to each other. Each shaped element is equipped with a protrusion made on its end surfaces along the perimeter with a bevel directed inside the surface of the element with an angle of inclination of 40-50°, and a height of 0.4-0.6 of its thickness. The shaped elements are connected at their ends to each other to form a joint of projections with bevels in mutually opposite directions.

EFFECT: reliable protection of the protected object from the effects of sub-caliber bullets.

2 cl, 7 dwg, 1 ex

Description

The invention relates to means of body armor and can be used independently or as part of body armor or other technical means of protecting a person from being hit by a bullet or other moving object with high kinetic energy. Progress in the creation of highly effective lethal weapons and the resulting increase in requirements for armor protection led to the creation of multi-layer combined armor. The ideology of combined protection consists of a combination of several layers of dissimilar materials with priority properties, including a front layer made of extra-hard materials and a high-strength, energy-intensive back layer. Ceramics of the highest hardness category are used as materials for the front layer, and its task is reduced to the destruction of the hardened bullet core due to stresses arising during high-speed interaction of the core with the ceramics. The back, retaining layer is designed to absorb kinetic energy and block fragments formed as a result of the impact interaction of a bullet with ceramics.

An armored structural element used as armor is known (German application No. 4005904, IPC F41H 5/04, publ. 08.29.1991), containing shaped elements made of ceramics, with end surfaces adjacent to each other, fixed on a substrate.

One of the main disadvantages of an armored element is that a sub-caliber bullet hitting the joint between ceramic elements leads to intense destruction of their end surfaces in the impact zone. This destruction is also enhanced by the influence of edge effects, while the gap in the joint between the plates increases, and the bullet pierces the layers of the armored element through and through.

Armor protection against the effects of sub-caliber bullets is known (see RF patent No. 2308660, IPC F41H 5/04, publ. 10/20/2007, Bulletin No. 29), containing shaped elements made of ceramics, joined by end surfaces to each other, end surfaces of shaped elements made of ceramics with a complex profile, the middle part is made with a bevel, the angle of inclination of which is selected 10-25°, the bevels of each pair are made in mutually opposite directions, and the length of each bevel is chosen such that when joining elements made of ceramics with opposite directions of the bevels, front ones are formed and rear gaps with a depth of 0.2-0.4 and a width of 0.04-0.15 of the thickness of the ceramic elements, and the total length of the joined ceramic elements, formed along the continuation of the bevel line, is at least 0.7 of the thickness of the ceramic elements .

One of the main disadvantages of armor protection is the reduced strength of the end sections (surfaces) of ceramic elements due to the fact that the impact of a damaging element, especially a sub-caliber bullet, in the joint between the plates leads to intensive destruction of their end surfaces in the impact zone. This destruction occurs due to the fact that the end surfaces of the ceramic shaped elements are made with a bevel. The bevel angle is chosen to be 10÷25°. The bevels of each pair of ceramic elements are made in mutually opposite directions, which reduces the strength and protective properties of the end sections (surfaces) of the ceramic elements, since the end sections do not consist of a monolithic ceramic element, but of two halves with a 2-fold reduced strength compared to the strength of monolithic ceramics. When a bullet hits such an end section, the bullet first pierces one half of the thickness of the joint, and then the second half of the joint, which significantly reduces the effectiveness of protection due to such gradual destruction of individual layers. As a result, the bullet pierces the joined ceramic elements with bevels and the substrate right through.

In addition, joining ceramic elements with bevels is a rather difficult task when assembling substrates for body armor and large armor panels for military equipment, because The bevels on 4 sides of the armor element must be accurately aligned with adjacent armor elements that also have bevels. The presence of bevels makes it necessary, in contrast to armor elements without bevels, to produce several standard sizes of armor elements with bevels, which complicates and increases the cost of producing armor protection.

The objective of the proposed solution is to increase the structural strength of ceramic elements and the protective properties of armor protection against the effects of sub-caliber bullets from rifle systems by strengthening the joint profile of the end surfaces of ceramic elements by increasing the thickness of the ceramic at the edges of the ceramic elements along the entire perimeter and changing the trajectory of the bullet when it hits in areas where ceramic elements join each other.

The technical result is achieved by the fact that in armor protection containing shaped elements made of ceramics, fixed on a substrate and joined by their end surfaces to each other, each shaped element is equipped with a protrusion made on its end surfaces along the perimeter with a bevel directed inside the surface of the element with an inclination angle of 40 -50° and a height of 0.4-0.6 of its thickness, while the shaped elements are connected at their ends to each other to form a joint of protrusions with bevels in mutually opposite directions.

When a bullet hits the armor protection in the end zone directly into a protrusion with increased thickness, the tip of the bullet begins to collapse and disintegrate into fragments, losing its kinetic energy, its flight trajectory does not change. There are dents in the substrate, but there is no through penetration. When a bullet hits the end zone in the bevel of the protrusion, its flight trajectory changes, the bullet partially fragments, deviates from the original direction of movement, begins to turn around, the sub-caliber bullet turns around and does not penetrate the armor protection. The substrate receives minor local damage, without penetration of the armor protection.

The design of the armor protection is implemented in such a way that the joints between adjacent armor elements become more durable and bullet-resistant from the point of view of reducing the destructive ability (fragmentation) of a bullet when it is introduced into the protective layers. The angle of inclination of the bevel of the end surfaces of the ceramic elements is selected from the condition of implementing a change in the trajectory of the bullet by turning it when it hits the bevel.

The most optimal from the point of view of the best protective and operational properties of armor protection is the presence of protrusions with bevels directed inside the surfaces of ceramic elements, and a height of 0.4-0.6 times the thickness of the ceramic elements and an angle of inclination of the bevels of 40-50°.

Thus, the claimed technical solution provides reliable protection of the protected object from the effects of sub-caliber bullets of rifle systems due to the reinforced edges of the armor elements in the form of protrusions with bevels directed inside the surfaces of these ceramic armor elements, and when connecting adjacent elements with their ends to each other, they form a joint of protrusions with bevels in mutually opposite directions.

The proposed technical solution is illustrated by drawings, where in Fig. 1 shows a top view of a shaped ceramic element, FIG. 2 shows a cross section of a shaped ceramic element with protrusions and bevels; FIG. Figure 3 shows a general view of the armor protection in cross section at the moment the sub-caliber bullet touches the upper part of the protrusion with a bevel; Fig. 4 shows a general view of the armor protection in cross section at the moment of destruction of the sub-caliber bullet after impact on the upper part of the protrusion with a bevel; in Fig. Figure 5 shows a cross-sectional view of the armor protection at the moment the sub-caliber bullet touches the middle part of the bevel at the protrusion when exposed to the sub-caliber bullet; Fig. 6 - shows a general view of the armor protection in cross section at the moment of destruction of the sub-caliber bullet after impact on the middle part of the bevel at the protrusion, in Fig. Figure 7 shows a view of the arrangement of shaped ceramic elements with beveled protrusions. In fig. 1-7 are indicated by letters and numbers:

1 - shaped elements made of ceramics with beveled protrusions;

2 - protrusions with bevels on the end surfaces of shaped ceramic elements;

3 - angle α between the end surface of the ceramic shaped element and the inner surface of the protrusion with a bevel;

4 - substrate;

5 - sub-caliber bullet;

6 - fragments of ceramic particles of the destroyed protrusion;

7 - fragments of the destroyed tip of a sub-caliber bullet;

H - thickness of shaped ceramic elements;

h - height of the protrusion with a bevel;

The armor protection (Fig. 1-7) contains shaped elements 1 made of ceramic fixed on a substrate 4, joined by their end surfaces to each other. The end surfaces of the shaped ceramic elements 1 are made with protrusions 2 with a bevel, while the angle of inclination of the 3 bevels is 40-50°. The protrusions 2, when connecting each pair of shaped ceramic elements 1 with their end surfaces to each other, form a joint of protrusions with bevels in mutually opposite directions. In this case, the height h of each protrusion 2 is chosen equal to 0.4-0.6 of the thickness H of the ceramic elements 1.

Let's consider two possible situations of shelling of the proposed armor protection design.

1. When a bullet hits the armor protection, it does not penetrate into the ceramics, since ceramics have a significantly higher hardness compared to the hardness of the bullet. Therefore, at the initial moment, the destruction of the bullet occurs due to the generation of high stresses in it that arise when braking against a ceramic barrier and complex wave processes that arise, with the help of which elastic energy is partially transferred to the substrate with its subsequent absorption and dissipation. The degree of bullet destruction is mainly determined by the interaction time until the ceramic is destroyed. If a sub-caliber bullet 5 hits the upper part of the protrusion 2 with bevels of ceramic elements 1, the bullet tip is destroyed into separate fragments 7 and at the same time the protrusion 2 of elements 1 is destroyed with fragments of ceramic particles 6 scattering in different directions. In this case, the substrate 4 receives local damage in in the form of a depression, but without through penetration.

2. If a sub-caliber bullet 5 hits the middle part of the protrusion 2 with bevels of ceramic elements 1, the bullet tip is destroyed into separate fragments 7 and its stability is lost. At the same time, the protrusion 2 of elements 1 is partially destroyed with fragments of ceramic particles 6 scattering in different directions. In this case, the bullet 5 deviates from the original direction of movement and begins to unfold. As the rotation angle increases from 0 to 90°, the projected area of the bullet increases by 2.5 times, and at the same time, the specific shock impulse (the ratio of the bullet energy to the projection area) decreases to the same extent. With an increase in the angle of rotation of the bullet, not only the degree of penetration of armor protection decreases, but also the depression in the barrier substrate. Ensuring that the bullet turns leads to a significant reduction in its penetration ability. In this case, the process of its destruction intensifies and part of the destroyed sub-caliber bullet 5 reaches the substrate 4 of the armor protection. When interacting with the substrate 4, it is completely inhibited. In this case, the substrate 4 receives minor local damage without through penetration.

The introduction of bevels on ceramic plates leads to the fact that at optimally selected angles of 40-50°, maximum energy dissipation occurs in the ceramic element, even if a bullet hits the joint, which leads to a lower rate of departure of ceramic fragments and fragments of the heat-strengthened core after overcoming the ceramic barriers, which allows the use of a substrate of less thickness and, accordingly, less weight compared to structures without bevels.

If the bevel angle is greater than 50°, then the probability of penetration of the ceramic element increases, since the absorption of the kinetic energy of the bullet in the ceramic plate at the junction decreases, which leads to less energy dissipation in the ceramic element, its destruction and deformation of the substrate. If the bevel angle is less than 40°, then this will not lead to the bullet turning, but will increase the probability of penetration and reduce the armor resistance of the armor protection. The maximum absorption of the kinetic energy of the bullet in the ceramic plate at the joint is achieved at a bevel angle of 45°. The bevel angle of the end surfaces of the ceramic elements was selected based on the conditions for the reversal of the sub-caliber bullet and non-penetration of armor protection.

An armor panel made of shaped elements made of ceramics with protrusions with bevels can be made either in a flat version (Fig. 7) or with a rounded radius of 410 mm. The armor panel on the outside can be filled with polyurethane and covered with technical fabric to reduce the scattering of ceramic fragments when hit by a bullet.

The implementation of the proposed armor protection design is confirmed by the following execution example.

Example

The armor protection contains shaped elements 1 made of aluminum oxide ceramics with a thickness of H-7 mm, joined at the end surfaces to each other. The end surfaces of the shaped ceramic elements 1 are made with protrusions 2 with bevels (Fig. 1). The height h of the protrusions 2 is selected with a coefficient of 0.5 from the thickness H of the ceramic elements 1 (Fig. 1) and is 3.5 mm. The angle α of the bevel at the protrusions is chosen to be 45°. The bevels of each adjacent pair of shaped ceramic elements 1, when connected by end surfaces with protrusions along the entire perimeter, are directed in opposite directions from each other (Fig. 3-6). When connecting the end surfaces of elements 1 made of ceramics with opposite directions of the bevels of the protrusions 2, depending on the particular arrangement of elements 1, joints of various configurations and different lengths are formed on the joined adjacent elements 1 made of ceramics. The substrate is made of supermolecular polyethylene.

Body armor can be manufactured according to protection classes 4, 5, 6 and 6A.

The joints formed on the front surface of the armor protection when connecting adjacent adjacent ceramic elements 1 become, due to the protrusions with bevels in mutually opposite directions, more durable compared to the joints of the prototype. The calculations confirmed the claimed technical result: the most optimal from the point of view of increasing bullet resistance and operational properties of armor protection are the height h of each protrusion 2 with a coefficient of 0.4-0.6 from the thickness H of ceramic elements 1 and the angle of inclination 3 of the bevels 40-50° .

Thus, the claimed technical solution provides reliable protection of the protected object from the effects of sub-caliber bullets from rifle systems due to a more durable configuration (shape) of the end surfaces of ceramic elements and joining them together when arranging shaped ceramic elements with beveled protrusions, as well as increasing bullet resistance and the effectiveness of armor protection.

Claims (2)

1. Armor protection containing shaped ceramic elements fixed on a substrate, joined by their end surfaces to each other, characterized in that each shaped element is equipped with a protrusion made on its end surfaces along the perimeter with a bevel directed inside the surface of the element with an inclination angle of 40-50 ° and a height of 0.4-0.6 of its thickness. 2. Armor protection according to claim 1, characterized in that the shaped elements are connected at their ends to each other to form a joint of protrusions with bevels in mutually opposite directions.

Images