DE19856597A1 - Protective armor plating has a molded body made of fabric, a knitted fabric or similar fibrous material made of carbon which is impregnated with silicon to convert to carbon fiber-reinforced silicon carbide - Google Patents

Abstract

Protective armor plating comprises a molded body (10) made of a bullet-proof material, and a backing (20) to hold the molded body and to form a surface structure. The molded body is made of fabric, a knitted fabric or similar fibrous material made of carbon which is impregnated with silicon to convert to carbon fiber-reinforced silicon carbide.

Description

The invention relates to protective armor according to the Preamble of claim 1 and a method for Manufacture of such protective armor.

In particular, the present invention is about a ballistic lightweight protective armor.

DE 34 26 457 C2 is bullet-proof plate materials as a projectile sheet with a textile Laminate for bulletproof vests, shields, armor plates and the like for holding bullets or the like known with high energy. To at the lowest possible Weight a variety of close shots, especially hard core bullets at high speed and to render high impact energy ineffective is in the publication proposed a first binder between a metallic or ceramic front layer and to use an underlying aramid laminate, the Adhesion at least 50% above the adhesion of a second binder, which lies between the layers of Laminates is used. The liability of the first binder be at least 60 N / 5 cm. The Binder with the higher adhesion should be used  of ceramic tiles cause the destroyed tiles with their remaining mass with the top aramid Fabric layer remains connected. The surrounding tiles should essentially cannot shift. As a result of This adhesive catches the high adhesion at the Destruction of the forces occurring on the tiles and gives them overall to the composite structure of the aramid protection package further. For this reason, the document also suggested between the tiles in the columns as well to use the binder with high adhesiveness to thereby on the one hand the friction between the edges of the To reduce tiles and on the other hand the elastic Transfer of forces to the whole without tile pressure Promote tile package. The well-known armor is right elaborate to manufacture and despite a high Basis weight only an insufficient protective effect.

DE 29 43 680 A1 is a plate-shaped armor element known which is a plate from a bullet-breaking Hard material has a bullet-resistant on the back Support fabric is arranged. As a bullet-resistant support special aramid fiber fabrics are proposed, the several form loosely forged layers and only weakly with each other are connected. This support fabric has the task of being a shelling destroyed or deformed hard material in Keep the overall structure together. Here too is the Protective effect in spite of high basis weight not sufficient.

From DE 35 08 848 A1 a tank element is known that a top layer of mosaic joined together Has ceramic hardboard. This top layer is connected to a carrier arranged underneath, the represents an energy absorbing layer and only so stiff is trained that he is just the association with the Hardboard can carry. At the same time, the  Carrier be formed as an energy-absorbing layer, the is relatively large-pored to penetrate the projectile in the armor plate has to push less material away. The low rigidity of the beam is due to another Supports made of metal or plastic added. One on that Armor-piercing projectile shatters the Hardboard and is together with the hardboard decelerated by the first and second carrier layers, wherein these two carrier layers deform. An impact resistant Envelope connects the hardboard together with the Backing layers and should provide all-round splinter protection Offer. The structure of this protective armor is relative expensive, the protective effect is despite the high basis weight not sufficient.

Starting from the above-mentioned prior art, it is a task of the present invention to show protective armor, which can be produced with relatively little effort and despite low basis weight a sufficient protective effect having.

This task is carried out by the protective armor Claim 1 solved. A method of making the Protective armor is described in claim 13.

The material used here is from, for example DE 42 07 009 known. A particularly preferred method for Production of the material or such materials are in particular also described in DE 193 50 468, on the Overall disclosure is specifically referred to here. The Material is also known as C / SiC material.

A very important feature of the C / SiC armor is its fracture / crack toughness, which with the same hardness compared to previously used monolithic hard ceramic materials such as. B. aluminum oxide, boron carbide, silicon carbide or silicon nitride is significantly higher. This higher fracture toughness means that when a bullet hits a bullet, the ceramic hard material layer is no longer completely destroyed. This lower destruction of the C / SiC coating in turn means that a much better protective effect can be achieved than is the case with powder-metallurgically produced monolithic ceramics. With the same protective effect, the C / SiC armor, which preferably has a density in the range of 2-2.7 g / cm ³ (depending on the fiber / matrix content), has a much lower basis weight than conventional steel or ceramic armor. This weight per unit area is less than 30 kg / m ² .

The C / SiC armor is gas and liquid tight and has no porosity. Compared to conventional armor, it also has excellent corrosion and weather resistance. The armor is particularly suitable as protection against small-caliber ammunition such as pistol and rifle ammunition. With a bullet stop effect for a caliber of 7.62 mmAP, the specific weight per unit area is below 30 kg / m ² . Splinter protection is also provided. This armor is therefore suitable for civilian protection of people, motor vehicles etc. as well as for the military sector (tanks, helicopters etc.). The C / SiC top layer is advantageous for use for armor in aggressive media and for camouflaging the devices provided with the armor. A suitable coating or compounding of the outer C / SiC layer can achieve an additional effect for protection during infrared and radar reconnaissance.

Preferably, the molded body made of C / SiC material has a higher hardness on its outer, incoming side, and a lower hardness on its inner side facing the backing structure with increased deformability and / or fracture toughness, which considerably increases the protective effect. Here, in particular, the molded body is designed so that it has a fiber quantity or fiber reinforcement that is adapted to its hardness and fracture toughness and varies with it from its outer side to its inner side. This means that the properties relevant to armor, such as hardness, speed of sound and density, can be adjusted to the respective threat through variations in the fiber / matrix content or the fiber reinforcement and the amount of SiC reacted in the carbon fiber structure. The hardness can e.g. B. between 1000-2400 N / m ² and the speed of sound between 8000-11 000 m / s by the type of fiber reinforcement or by the amount of fibers introduced into the carbon molded body and the infiltration parameters in the siliconization.

The backing structure is preferably selected from aramid Moldings, GRP moldings, polyethylene fiber moldings, CFRP moldings or metal moldings selected.

The application of the moldings to the backing structure is preferably carried out using a binder, particularly preferably by means of polyurethane.

The C / SiC molded body is preferably formed so that it a decreasing hardness from the outside in and increasing Has deformability or fracture toughness. This can be so happen that the molded body from at least two superimposed, preferably glued to each other Shaped bodies of different hardness and fracture toughness consists. Alternatively, but possibly also additionally (that is, with each of the superimposed shaped bodies) one from its outside to its inside in substantially continuously varying hardness or  

Fracture toughness can be provided by looking at the amount of fiber and / or fiber reinforcement for producing a gradient C / SiC composite varies.

The molded body has an outer contour designed in this way, preferably a rectangular or hexagonal outline on that other moldings are essentially complete are attachable to one another essentially to produce continuous armoring of the outer layer, the looks good in any form of overlay or one Can adjust the support structure. Furthermore, the Shaped bodies preferably shaped in this way, in particular beveled or concave or convex outer contours on that appropriately shaped further shaped bodies to each other on the Edges can be overlapped to ensure continuity to improve the outer layer. The attached to each other Shaped bodies are preferably together at their edges glued.

The fiber material is preferably with before infiltration Silicon brought into the shape of the finished molded body. This allows even more complicated shapes with everyone necessary recesses, any wall thickness, Wall thickness variations and sizes can be produced. The Manufacturing in the green state does not require high Tool costs and is not very expensive.

To make the protective armor, one works Carbon moldings, in particular with plates Carbon fiber reinforcement, especially short fiber and / or Felt reinforcement and / or fabric reinforcement so that they are have the desired dimensions and shapes.

This processing can be done using conventional machining techniques, in particular through  Turning, milling or sawing happen. These semi-finished products Carbon fiber reinforced carbon (C / C) are in an oven in the absence of oxygen, especially in a vacuum Temperatures over 1405 ° C heated and with silicon infiltrates. If it heats up again, it reacts Carbon from the moldings with the infiltrated Silicon at least partially to silicon carbide, so that (after cooling) the moldings carbon fiber reinforced silicon carbide. This Shaped bodies form ballistic protective plates that by means a binder, preferably by means of polyurethane Aramid sheets and / or GRP sheets and / or polyethylene fiber Molded articles and / or CFRP plates and / or metal plates, which serve as a backing structure, are glued on.

Preferably, two or more such C / SiC shaped bodies with different hardness or fracture toughness are glued to one another in order to form a composite body, since the fracture toughness (and decreasing hardness) increases in the direction of the backing structure. Alternatively (or additionally), both the infiltration with silicon and the density of the carbon fibers can be adjusted with a gradient in such a way that they result in increased fracture toughness (falling hardness) in each individual molded body. The infiltration with silicon is preferably carried out by the following process steps:

• - manufacture of a liquid or sticky binder, which is curable and doped with carbon;
• - Coating particles or groups of particles a silicon powder or silicon granules with the Binders for the production of donor silicon;  
• - Forms of the donor silicon according to the surfaces of carbon fiber reinforced carbon existing green body for the production of Dispenser silicon moldings;
• - Drying and curing of the donor silicon moldings;
• - Place the donor silicon molded body on the Green body;
• - Heating up the green body with applied Donor silicon moldings at temperatures at which Silicon melts and beyond until the carbon with the silicon to form silicon carbide responds;
• - Infiltrating the green body with donor silicon, the from the donor silicon moldings down to the Green body flows.

The amount of silicon donor can be set here that they lead to a complete siliconization of the Green body is not enough. The siliciding process is running then inevitably inhomogeneous. It is also possible that Infiltration of the green body with donor silicon in this way make that the green body in a bed (bathroom) from Donor silicon sets so that the molten silicon due to the wicking effect of the green body in this increases. This can also be done in a relatively simple manner predetermined gradient in terms of penetration with Silicon and the subsequent reaction of the carbon be adjusted with silicon so that the desired one Increase in fracture toughness (decrease in hardness) from one Surface of the shaped body to the other is ensured.

Exemplary embodiments of the invention are described below described in more detail by illustrations.

Here show:

Figure 1 shows a first preferred embodiment of the invention in a partial section.

Fig. 2 shows a second embodiment of the invention in a representation similar to that of FIG. 1 for explaining various possibilities of shaping the edges and

Fig. 3 shows a third preferred embodiment for explaining a multilayer or inhomogeneous structure.

In the following description, the same and equivalent parts used the same reference numerals.

The embodiment of the protective armor shown in FIG. 1 comprises molded C / SiC bodies 10 produced by the method described above, which are glued to a backing structure 20 by means of an adhesive film 13 . The edges 14 of adjacent molded bodies 10 are held together by adhesive films 12 . An elastic adhesive film 11 is provided on the surface (on the side coming to the projectile).

In Fig. 2 different forms of edges 14 , 15 or 16 are shown , which are used either to form flat structures ( 14 , 16 ) or to form curved structures ( 15 ). Many structures of this type are conceivable here, the protective armor according to the invention and the method according to the invention being particularly suitable for producing such structures, since the green bodies consist only of carbon and can therefore be shaped very easily using conventional tools (in particular machining). It is also possible not to produce planar shaped bodies 10 (as shown in the figures), but also to produce any curvatures by appropriately producing the carbon fiber-reinforced blanks.

The embodiment of the invention shown in FIG. 3 differs from the embodiments according to FIGS. 1 and 2 in that the molded bodies 10 are subdivided into an upper molded body 10 and a lower molded body 10 ', which each have different fiber contents. The upper molded body 10 on the projectile side has a lower fiber content and thus a greater hardness than the lower molded body 10 ', which in turn has increased fracture toughness. The connection between the upper and lower moldings can be made using an adhesive layer. It is also possible to stack the two shaped bodies 10 and 10 'on top of one another with the interposition of silicon and, as it were, to weld them together in the vacuum furnace after appropriate heating above the melting temperature of silicon. Finally, it is also possible (but hardly portrayable in the drawing) to produce the shaped bodies in such a way that they have a fiber content that changes gradually with the depth (in the direction of the backing structure 20 ) with increasing fracture toughness and falling hardness.

Reference list

10th

C / SiC molded body

11

Elastic adhesive film

12th

Adhesive film

13

Adhesive film

14-16

edge

20th

Backing structure

Claims (17)

1. Protective armor, in particular ballistic light-weight protective armor comprising:

• - At least one molded body ( 10 ) made of a bullet-proof material and
• - A backing structure ( 20 ) for holding the shaped bodies ( 10 ) together and for forming a flat structure, characterized in that the shaped body ( 10 ) consists of a woven fabric, knitted fabric, knitted fabric or similar fiber material made of carbon, which is infiltrated in a siliciding process Silicon is converted to carbon fiber reinforced silicon carbide.

2. Protective armor according to claim 1, characterized in that the shaped body ( 10 ) has a higher hardness on its outer, projectile side and a lower hardness with increased deformability and / or fracture toughness on its inner side facing the backing structure. 3. protective armor according to one of the preceding claims, characterized in that the molded body one, its hardness and fracture toughness adapted and with it from its outer side to on the inner side varying amount of fibers and / or Has fiber reinforcement. 4. Protective armor according to one of the preceding claims, characterized in that the molded body ( 10 ) consists of at least two superimposed, preferably glued molded bodies ( 10 , 10 ') of different hardness and fracture toughness. 5. armor according to one of the preceding claims, characterized in that the molded body one from its outer to its inner Page essentially continuously varying hardness and has fracture toughness. 6. protective armor according to one of the preceding claims, characterized in that the backing structure is selected from aramid Molded bodies, GRP molded bodies, polyethylene fiber Moldings, CFRP moldings, metal moldings. 7. Protective armor according to one of the preceding claims, characterized in that the molded body ( 10 ) on the backing structure ( 20 ) by means of a binder ( 13 ), preferably by means of polyurethane, is glued on. 8. Protective armor according to one of the preceding claims, characterized in that the shaped body ( 10 ) has such an outer contour, preferably a rectangular or hexagonal outer contour, such that further shaped bodies ( 10 ) can be used essentially without gaps. 9. Protective armor according to claim 8, characterized in that the shaped body ( 10 ) has such shaped, in particular beveled or concave or convex outer contours or edges ( 14 , 15 , 16 ) that correspondingly shaped further shaped bodies ( 10 ) one another at the edges ( 14 , 15 , 16 ) can be applied overlapping. 10. Protective armor according to one of claims 8 or 9, characterized in that the molded bodies ( 10 ) attached to one another are glued to one another at their edges ( 14 , 15 , 16 ) (adhesive film 12 ). 11. protective armor according to one of the preceding claims, characterized in that the fiber material before infiltrating with silicon in the shape of the finished molded body is brought. 12. Protective armor according to one of the preceding claims, characterized in that the molded body has a density of 2-2.7 g / cm ³ . 13. A method of manufacturing protective armor comprising the steps of:

• - Manufacture of at least one green body made of carbon, in particular carbon fiber-reinforced carbon, which is at least partially porous, the fibers in particular consisting of a woven fabric, knitted fabric, knitted fabric or similar fiber material made of carbon;
• - Heating the green body in an oven with the exclusion of oxygen, in particular in a vacuum to temperatures above 1405 ° C;
• - infiltrating the green body with liquid silicon;
• - Further heating of the green body with infiltrated silicon until the silicon has at least partially reacted with the carbon;
• - Cooling the moldings and sticking them onto a backing structure.

14. The method according to claim 13, characterized by the following further method steps:

• - Manufacture of a liquid and / or sticky binder that is curable and doped with carbon;
• - Coating particles or groups of particles of a silicon powder or silicon granulate with the binder for the production of donor silicon;
• - Apply the donor silicon to the green body before it is placed in the oven for heating.

15. The method according to claim 14, characterized in that the donor silicon before application to the green body shaped and optionally dried and / or is cured.   16. The method according to claim 13; characterized in that the green body for infiltrating silicon in a bath is made of silicon such that the silicon due to the wicking effect in the green body increases. 17. The method according to claim 13, characterized in that the silicon provided in such a deficit or the process of infiltration and silicification is stopped early that one in the vertical inhomogeneous structure arises.