Title:
Ceramic Armor Plate, an Armor System, and a Method of Manufacturing a Ceramic Armor Plate
Kind Code:
A1


Abstract:
A ceramic armor plate is proposed which is formed in one piece and which comprises a plurality of connected segments that are functionally separated by crack stoppers, whereby the crack stoppers serve to prevent the propagation of cracks from one segment to a neighboring segment.



Inventors:
Heidenreich, Bernhard (Asperg, DE)
Nedele, Martin (Reutlingen, DE)
Schulte, Ruediger (Stuttgart, DE)
Application Number:
11/561144
Publication Date:
06/07/2007
Filing Date:
11/17/2006
Assignee:
Deutsches Zentrum fur Luft-und Raumfahrt e.V.
Primary Class:
International Classes:
F41H5/02; F41H5/04
View Patent Images:
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Primary Examiner:
LEE, BENJAMIN P
Attorney, Agent or Firm:
ALSTON & BIRD LLP (CHARLOTTE, NC, US)
Claims:
1. A ceramic armor plate formed in one piece, comprising: a plurality of connected segments that are functionally separated by crack stoppers; wherein the crack stoppers serve to prevent the propagation of cracks from one segment to a neighboring segment.

2. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are integrated into the armor plate.

3. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are formed in the solid material of the armor plate.

4. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are produced when manufacturing the armor plate.

5. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are formed by recesses or from recesses.

6. A ceramic armor plate in accordance to claim 5, wherein the recesses are produced in the thickness direction of the armor plate.

7. A ceramic armor plate in accordance to claim 5, wherein the recesses are produced at an angle of between 15° and 45° with respect to a thickness direction of the armor plate.

8. A ceramic armor plate in accordance with claim 5, wherein the recesses do not extend through the entire thickness of the armor plate.

9. A ceramic armor plate in accordance with claim 5, wherein the crack stoppers are formed by grooves or from grooves.

10. A ceramic armor plate in accordance to claim 9, wherein the depth of the grooves lies in a range of between 0.05 to 0.9 of the thickness of the armor plate.

11. A ceramic armor plate in accordance to claim 5, wherein the recesses extend through the entire thickness of the armor plate.

12. A ceramic armor plate in accordance with claim 5, wherein the crack stoppers are formed by perforations or from perforations.

13. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are formed from cracks.

14. A ceramic armor plate in accordance with claim 13, wherein the cracks serving as crack stoppers run between an upper surface and a lower surface of the armor plate.

15. A ceramic armor plate in accordance with claim 14, wherein the cracks run at least approximately in the thickness direction of the armor plate.

16. A ceramic armor plate in accordance with claim 14, wherein there are provided covering layers between which the cracks extend.

17. A ceramic armor plate in accordance with claim 16, wherein the covering layers are made of C/C—SiC.

18. A ceramic armor plate in accordance to claim 16, wherein the covering layers are made of a material which has a lower coefficient of thermal expansion than the material between the covering layers.

19. A ceramic armor plate in accordance to claim 1, wherein the crack stoppers are in the form of defects.

20. A ceramic armor plate in accordance to claim 1, wherein the spacing between the crack stoppers lies in a range of between 5 mm and 100 mm.

21. A ceramic armor plate in accordance to claim 1, wherein the armor plate has a multi-layer structure.

22. A ceramic armor plate in accordance with claim 1, wherein the armor plate is produced from a carbide ceramic material.

23. A ceramic armor plate in accordance with claim 1, wherein the armor plate is produced from a silicon carbide ceramic.

24. A ceramic armor plate in accordance with claim 1, wherein the crack stoppers are formed prior to a ceramicization process.

25. A ceramic armor plate in accordance with claim 1, wherein the armor plate is produced by means of a carbon-containing preform.

26. A ceramic armor plate in accordance with claim 1, wherein the ceramic material of the armor plate is manufactured by means of a biomorphic material.

27. A ceramic armor plate in accordance with claim 26, wherein the biomorphic material contains cellulose.

28. An armor system comprising: at least one armor plate with a plurality of connected segments that are functionally separated by crack stoppers; wherein the crack stoppers serve to prevent the propagation of cracks from one segment to a neighboring segment.

29. An armor system in accordance with claim 28, wherein the armor system has a multi-layer structure.

30. An armor system in accordance with claim 28, wherein the at least one armor plate is arranged on a backing.

31. A method of manufacturing a ceramic armor plate, comprising: producing crack stoppers in an armor plate preform; and subdividing the armor plate into connected functional segments by the cracks stoppers.

32. A method in accordance with claim 31, wherein the crack stoppers are produced before the armor plate material is subjected to a ceramicization process.

33. A method in accordance with claim 31, wherein the crack stoppers are formed by the production of recesses.

34. A method in accordance with claim 33, wherein the recesses are produced by a mechanical material-working process.

35. A method in accordance with claim 33, wherein the recesses are produced by beam processing.

36. A method in accordance with claim 31, wherein the recesses are filled with a parting agent.

37. A method in accordance with claim 31, wherein the crack stoppers are produced in the form of cracks.

38. A method in accordance with claim 37, wherein cracks are produced by the process of connection to covering layers.

39. A method in accordance with claim 38, wherein the covering layers are made of C/C.

40. A method in accordance with claim 31, wherein the armor plate preform is a carbon-containing preform.

41. A method in accordance with claim 31, wherein a multi-layer structure is provided, wherein the layers are connected for the purposes of forming a one-piece armor plate during a ceramicizing process.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT Application No. PCT/EP2005/005172, filed May 12, 2005, and also claims the benefit of German Application No. 10 2004 026 515.1, filed May 19, 2004, both of which are incorporated herein by reference in their entirety and for all purposes.

BACKGROUND OF THE INVENTION

The invention relates to a ceramic armor plate. Furthermore, the invention relates to an armor system. The invention also relates to a method of manufacturing a ceramic armor plate.

An armor system is known from, for example, EP 0 810 415 B1 (DE 697 07 560 T2). An armor system may comprise a plurality of ceramic tiles arranged in a tile layer. The purpose of the ceramic tiles is to destroy the core of a striking projectile due to the hardness of the ceramic.

SUMMARY OF THE INVENTION

In accordance with the invention, a ceramic armor plate and an armor system that can be produced in a simple manner are provided. A ceramic armor plate is formed in one piece and comprises a plurality of connected segments which are functionally separated by crack stoppers, wherein the crack stoppers serve to prevent the propagation of cracks from one segment to a neighboring segment. In accordance with the invention, a one-piece armor plate incorporating integrally produced crack stoppers is provided. The manufacturing process is therefore considerable simplified since there is no need to manufacture a plurality of individual tiles which must then be joined together, but rather, a whole plate covering a larger surface area is manufactured in an integral manner. Since a joining process is not necessary, the problems associated therewith are also avoided. For example, deformation and a decrease in size can occur when manufacturing ceramic plates. If ceramic tiles are to be joined, then this requires a complex manufacturing process in order to join them such that the tiles match precisely with only small width gaps between the tiles. In the case of the ceramic armor plate in accordance with the invention, however, such a joining process is not necessary and, thus, the manufacturing process is less complex.

The crack stoppers can be formed in a simple manner during the manufacturing process; for example, by means of cracks produced in a defined manner or by means of grooves which are formed before the ceramicization process. It is thereby possible to produce the functional segments such that they are defined for the desired field of application.

It is also possible to manufacture a ceramic armor plate with a defined curvature for certain fields of application. If individual tiles are joined, then it is considerably more difficulty to produce such a curved arrangement since the tiles in the composite tile structure may be of different curvature.

Compared with a composite tile structure, there are a multiplicity of ways for forming the armor plate due to the integration of the crack stoppers into the armor plate. The armor plate of the inventon may be formed in multiple layers for example, whereby the crack stoppers can be arranged in different ways in the differing layers. Therefore, there are a large number of ways for controlling and adjusting the course of a crack in the event of bombardment and, thus, controlling the ballistic characteristics of the armor plate.

Improved protection is also provided as a result of the crack stoppers in the event of multiple bombardment. In addition, different segment geometries can be realized, such as rectangles, hexagons, curved segments, etc., for example.

It is especially advantageous for the crack stoppers to be integrated into the armor plate. Consequently, the armor plate can easily be manufactured and an armor system comprising at least one armor plate in accordance with the invention can also be manufactured in a simple manner.

In particular, the crack stoppers are formed in the solid material of the armor plate so that separate tiles that have to be joined at a later time do not need to be provided. The process of manufacturing the armor plate is thereby considerably simplified, whereby a large surface area can be manufactured in a simple manner. In particular, the crack stoppers are produced when manufacturing the armor plate.

In one embodiment, the crack stoppers are formed by recesses and/or from recesses. The recesses can be produced in a particularly simple manner prior to the process of ceramicizing an armor plate preform. They can be arranged in a defined manner. For example, a grid of recesses can be produced. Furthermore, the recesses can be produced with defined depths. When the armor plate has been manufactured, the recesses are not necessarily still present. For example, they are filled with a parting agent before infiltrating them with carbide-forming materials (such as silicon for the siliconizing process). Their crack stopping function is still maintained however, since the material of the segments (SiC for example) exhibits a significantly higher speed of sound than the material of the parting agent in the recesses (for example BN, C, SI). It is also possible to have a filling consisting of a carbon-rich paste which is not converted to SiC during the siliconizing process, or one consisting of pure silicon.

In particular, the recesses are produced in the thickness direction of the armor plate. The armor plate is thus divided into functional segments, whereby the segments are contiguous. The recesses prevent propagation of a crack beyond a segment if a segment experiences an impact such as the impact of a projectile for example.

It is also possible for the recesses to be produced at an angle of between 15° and 45° with respect to a thickness direction of the armor plate. This can be advantageous for certain fields of application.

Provision may be made for the recesses to be non-penetrating. For example, crack stoppers are formed by grooves and/or from grooves. Such grooves can be produced in a simple manner, for example, by a milling process or laser working or a water-jet cutting process. It is preferable for the depth of the grooves to lie in a range of between 0.05 and 0.9, and preferably between 0.1 and 0.6 of the thickness of the armor plate. Consequently, a crack stopping effect can be obtained on the one hand and a one-piece armor plate can be formed on the other.

It is also possible for recesses extending through the plate to be provided in the thickness direction. To this end, the crack stoppers are formed by perforations and/or from perforations for example.

It is also possible for the crack stoppers to be formed by cracks. Such cracks can be produced in a defined manner, in that, for example, cover plates (covering layers) are placed on a solid material perform, these plates having a different coefficient of thermal expansion than that of the solid material preform. An integral composite material having cracks formed therein is produced in the subsequent ceramicization process.

In particular, the cracks serving as crack stoppers run between an upper surface and a lower surface on the armor plate. In consequence, the armor plate can be divided into functional segments, whereby the propagation of cracks beyond segments is stoppable.

It is expedient if the cracks run at least approximately in the thickness direction of the armor plate. In consequence, the armor plate can be divided into segments which correspond to a composite tile structure having joints between the tiles although the armor plate is formed in one piece.

It is expedient if covering layers are provided between which the cracks extend. The armor plate is thereby covered by a crack-free covering layer at the upper surface and lower surface thereof. Due again to the covering layers, it is then possible to produce defined cracks during the process of manufacturing the armor plate. The covering layers are made of C/C—SiC for example. To this end, for example, C/C preforms are fixed on the lower surface and the upper surface of a porous C preform, and this is then followed by a siliconizing process. Covering layers consisting of C—C—SiC can thereby be formed. Due to the different material properties, a crack structure can be produced during the siliconizing process or during the process of cooling the body infiltrated with silicon, whereby the cracks run between the covering layers. Again, the functional segments can be produced thereby. The size of the segments can be established by using different layers having differing coefficients of the thermal expansion.

In principle, it is possible for the crack stoppers to be in the form of defects such as cracks for example.

It has proved to be expedient if the distance between the crack stoppers lies in a range of between 5 mm and 100 mm, and preferably in a range of between 30 mm and 50 mm.

It can be expedient to provide a multi-layer structure. The layers are thereby formed together in one piece. For example, a plurality of layers are joined together in one piece (in situ) in the course of the ceramicization process (such as by in infiltration of liquid silicon, i.e., a siliconizing process for example).

In one embodiment, the armor plate is made of a silicon carbide ceramic. This material has a high hardness so that a projectile striking it is destroyed. It is also conceivable for the armor plate to be manufactured from other carbide forming metals such as titanium or chrome.

It is expedient in certain embodiments for the crack stoppers to be introduced into the ceramic material of the armor plate and embedded therein. There is, thus, no connection between the crack stoppers and the surfaces of the plate.

The armor plate can be manufactured, in particular, from a carbon-containing preform. Such a preform is workable in a simple manner. It is capable of being at least partially ceramicized. For example, this preform is manufactured by means of graphite powders and bonding agents.

The armor plate in accordance with the invention can be manufactured economically, particularly where the ceramic material of the armor plate is manufactured by means of a biomorphic material and, in particular, a cellulose containing material. Appropriate manufacturing processes are described in the not prior published German Application No. 103 29 822.3, dated Jun. 30, 2003, or in DE 199 47 731 A1. Express reference to these documents is made.

The armor plate in accordance with the invention can be utilized advantageously in an armor system which comprises at least one armor plate in accordance with the invention. A corresponding armor system has, in particular, a multi-layer structure. An example is described in EP 0 810 415 B1, which is incorporated by reference herein. Instead of a plurality of tiles as is described therein, at least one armor plate in accordance with the invention can be used.

In particular, the at least one armor plate is seated on a backing (a structural supporting layer) which is preferably made of a lightweight construction material such as aluminium or carbon KEVLAR® or aramid.

Furthermore, in accordance with the invention, a method for the manufacture of a ceramic armor plate is provided which can be carried out in a simple manner. In accordance with the invention, crack stoppers are produced in an armor plate preform and the armor plate is divided into contiguous functional segments by the crack stoppers. In accordance with the invention, the crack stoppers (for the armor plate being manufactured) are formed, namely, in an armor plate preform into which they can be introduced without complication in the course of the manufacturing process for the ceramic armor plate. This results in an easy manner of fabrication, whereby defined functional segments are obtainable by means of a defined process of producing crack stoppers.

The method in accordance with the invention has the advantages already described in connection with the ceramic armor plate in accordance with the invention. Further advantageous embodiments of the method in accordance with the invention were likewise explained hereinbefore in connection with the ceramic armor plate in accordance with the invention.

In principle, it is possible for the crack stoppers to be introduced after the ceramicization process. However, the crack stoppers are typically produced before the armor plate material is subjected to the ceramicization process. It is then possible for the crack stoppers to be formed in the material by means of a machining process for example. In the stage before the ceramicization process, the material is less hard by far than after the ceramicization process and is therefore more easily worked.

For example, the crack stoppers are formed by the production of recesses. These can be produced in a simple manner such as to have a defined arrangement and shape by means of a mechanical material-working process such as a machining process (e.g., milling, boring, grinding, etc.) and/or beam processing such as laser working or water-jet machining.

Provision may be made for the recesses to be filled with a parting agent. The purpose of the parting agent is to ensure the crack stopping function for the finished armor plate (which is subjected to a ceramicization process). In particular, the parting agent serves to prevent wetting with a carbide-forming material during the ceramicization process. For example, the filling process can be effected using a carbon-rich paste. Carbon webs can thereby be produced in a ceramic armor plate. The filling process could also be effected using silicon.

It is also possible for the crack stoppers to be produced in the form of defined cracks. For example, the cracks are produced by the connection to cover plates. These cover plates are placed on a preform prior to the ceramicization process. A one-piece connection of the cover plates is effected by means of the ceramicization process, for example by means of a siliconizing process, whereby cracks are producible. In particular, the cover plates are made of C/C, i.e., made of carbon fiber reinforced carbon.

It is also expedient to provide a multi-layer structure wherein the layers are connected in situ for forming a one-piece armor plate during the ceramicization process. The characteristics of the ceramic armor plate can thus be controlled or adjusted in a defined manner. For example, crack stopper structures can be formed in respective individual layers. Thus, a breakage cascade resulting from bombardment can be controlled in order to increase the ballistic protection.

The following description of preferred embodiments taken in conjunction with the drawings serves to provide a more detailed explanation of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to assist the understanding of certain embodiments of the invention, reference will now be made to the appended drawings, which are not necessarily drawn to scale, and wherein:

FIG. 1 shows a schematic illustration of a first exemplary embodiment of a ceramic armor plate in accordance with the invention;

FIG. 2 shows a schematic illustration of a second exemplary embodiment;

FIG. 3 shows a sectional view of the armor plate in accordance with FIG. 1;

FIG. 4 shows a sectional view of a third exemplary embodiment;

FIG. 5 shows a sectional view of a fourth exemplary embodiment;

FIG. 6 shows a sectional view of a fifth exemplary embodiment;

FIG. 7 shows a sectional view of a sixth exemplary embodiment; and

FIG. 8 shows a perspective partial sectional view of an exemplary embodiment of an armor system that comprises a ceramic armor plate in accordance with the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention now will be described more fully hereinafter. However, this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. As used in this specification and the claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

A first exemplary embodiment of an armor plate in accordance with the invention is schematically shown in FIG. 1 and bears the general reference 10 therein. The armor plate 10 is made of, for example, a silicon carbide ceramic.

To form the armor plate 10 of FIG. 1, a carbon-containing armor plate preform is manufactured. For the purposes of manufacturing the armor plate preform, a cellulose-containing material, for example, is used and a porous preform is manufactured therefrom. The preform is then converted by means of pyrolysis into an open-pored carbon body. Grooves 12 are formed in this preform prior to the ceramicization process. For example, a rectangular grid 14 of grooves 12 is produced. Crack stoppers, which prevent the propagation of cracks, are formed by the grooves 12.

It is also possible for the grooves or recesses 12 to be formed in a green body prior to the pyrolysis process, thereby simplifying the mechanical treatment process. The gap between neighboring segments is made smaller by virtue of the contraction occurring during pyrolysis. In the case of a green body incorporating recesses or grooves, the danger of delamination occurring during the pyrolysis process is reduced because the gases can escape more quickly via the recesses or grooves.

The grooves 12 subdivide the armor plate 10 into individual segments 16 that are connected such that the armor plate 10 is formed in one piece. The segments 16 are functionally defined. They are bounded by grooves 12. The grooves 12 prevent cracks which develop in a segment (in the segment 18 for example, due to the impact of a projectile) from propagating to neighboring segments 20a, 20b, 20c, 20d, 20e, 20f, 20g, 20h.

As noted above, the grooves 12 can be formed after the pyrolysis process and before the armor plate preform is subjected to the ceramicization process. This is effected by subjecting the material to a machining processing such as milling and/or laser working for example. Subsequent to the formation of the grooves 12, the armor plate preform is subjected to a siliconizing process wherein the armor plate preform is converted into a silicon carbide armor plate by infiltration of materials comprising silicon.

The grooves 12 extend in the thickness direction d of the armor plate 10. The thickness of the armor plate 10 is D (FIG. 1). The depth of the grooves 12 preferably lies in a range of between 0.1 and 0.6 times the thickness D of the armor plate 10. The typical depth of the grooves 12 is approximately 6 mm. The segments 16 defined by the grid 14 of grooves 12 has typical transverse dimensions (perpendicular to the thickness direction d) of between 30 mm and 50 mm.

For the purpose of manufacturing the armor plate perform, provision may be made for a cellulose-containing powder to be used as the starting constituent. A suitable manufacturing process is disclosed in the not prior published German patent application No. 103 29 822.3 dated Jun. 30, 2003, assigned to the same applicant and incorporated by reference herein. As described in this reference, a porous preform is made from a cellulose-containing material, the porous preform is converted into an open-pored carbon body by means of pyrolysis, and the open-pored carbon body is converted into a carbide ceramic incorporating silicon, in particular, a silicon carbide ceramic by infiltration of materials incorporating silicon, wherein a cellulose-containing powder is used as the starting constituent for the production of the preform. In the above-cited application, there are also disclosed components which comprise carbon bodies that are infiltrated by materials incorporating silicon and thereby substantially ceramicized into a carbide incorporating silicon, and in particular into silicon carbide, whereby the carbon body has a substantially homogeneous porous structure due to the use of a cellulose-containing powder and a bonding agent as the starting constituents.

The grooves 12 can be filled with a parting agent such as boron nitride prior to the siliconizing process. Silicon does not wet the prating agent. Thus, defects, which also serve as crack stoppers, will remain from the siliconizing process.

In accordance with the invention, crack stoppers are formed in the armor plate 10. In the exemplary embodiment in accordance with FIG. 1, these crack stoppers are the grooves 12 which are formed in grid-like manner. If a projectile hits a segment, the segment 18 for example (hatched for illustrative purposes in FIG. 1), then the grooves 12 surrounding the segment 18 prevent cracks from propagating into the neighboring segments 20a, b, c, d, e, f, g, h.

The armor plate 10 can be manufactured integrally and the crack stoppers are formed in the armor plate 10 in an integral manner. It is also possible for example, for the armor plate 10 to be manufactured with appropriate curvatures. In the exemplary embodiment in accordance with FIG. 1, non-penetrating recesses are formed in an armor plate preform by the grooves 12.

It is also possible, as is shown with the aid of a second exemplary embodiment 22 in FIG. 2, for recesses 24 in the form of perforations to be formed in an armor plate preform prior to the ceramicization process. These perforations likewise serve as crack stoppers in order to prevent the propagation of cracks from a segment 26 to the neighboring segments.

A sectional view through the armor plate in accordance with FIG. 1 is schematically illustrated in FIG. 3. One can perceive the crack stoppers which are in the form of grooves 12 formed in the surface. A surface 30 from which the grooves 12 extend is preferably located opposite an outer surface 28 of the armor plate 10. The outer surface 28 is preferably directed outwardly when in use.

As shown schematically in FIG. 4, wherein it bears the general reference 32, it is also possible for an armor plate to be built up from a plurality of layers, for example, from a first layer 34a, a second layer 34b, and a third layer 34c. The layers 34a, 34b, 34c are connected integrally together so that the armor plate 32 is formed in one piece. The layers 34a, 34b, 34c are produced from separately pyrolyzed preforms for example, and thereafter the corresponding layers are connected to one another to form one piece by the siliconizing process.

Crack stoppers in the form of grooves 36 are formed in the layers 34a, 34b, 34c before the ceramicization process (i.e., siliconizing process). The formation of the grooves is, in principle, effected in the manner described above in connection with the first exemplary embodiment. Thus, functional segments 38a, 38b, 38c are produced in each layer. The segments in each layer are thereby functionally separated by the grooves 36 serving as crack stoppers. The grooves 36 have a typical depth of approximately 3 mm.

Provision may be made for the segments of neighboring layers to overlap. For example, the segments 38b of the layer 34c in each case overlap the segments 38c and 38a of the layers 34a and 34c.

In a further exemplary embodiment of an armor plate, which is schematically illustrated in FIG. 5 and referenced 40 therein, grooves 42 and 44 are formed such as to extend from opposite surfaces 46, 48. The grooves 42, 44 are non-penetrating and are mutually displaced with respect to a direction transverse to the thickness direction d. Functional segments are thereby also formed in the armor plate 40, whereby the grooves 42, 44 serving as crack stoppers prevent the propagation of cracks beyond a segment in the event that a particular segment is hit by a projectile for example.

In a further exemplary embodiment of an armor plate, which is shown in FIG. 6 and bears the general reference 50 therein, there is provided a multi-layer structure comprising a first layer 52a, a second layer 52b, and a third layer 52c. These layers consist of silicon carbide layers, for example, which are integrally connected together by means of a siliconizing process. Hereby, provision may be made for the middle layer 52b to comprise cracks 54 which are produced in a defined manner. The cracks run at least approximately parallel to a thickness direction of the armor plate 50. The cracks 54 serve as crack stoppers. The armor plate 50 is subdivided into functional segments 56 by means of these cracks, whereby the particular segments are bounded by cracks. The cracks 54 are each in the form of a kind of predetermined breaking point and prevent the propagation of cracks 54 beyond a segment if, for example, cracks occur in the segment 56 due to the impact of a projectile. The cracks could also run at an angle of 15° to 45° or be perpendicular to the thickness direction. The armor plate 50 is joined in situ in multiple layers with the cracks 54 being in the form of internal defects, i.e., the armor plate 50 is formed in one piece.

It is also possible, as shown in FIG. 7 with the aid of a further exemplary embodiment of an armor plate 58, for the cracks 60 to be formed as crack stoppers in a silicon carbide ceramic solid material 62 for example, whereby the solid material 62 is located between covering layers 64, 66 consisting of C/C—SiC. The covering layers 64, 66 are produced from covering layer preforms consisting of C/C for example, these being connected to the solid material preform for the siliconizing process. Due to the siliconizing process, defined cracks can thereby be formed between the covering layers 64, 66 in the silicon carbide ceramic solid material 62 and in particular, during the cooling process. The covering layers 64, 66 have a typical thickness of approximately 1 mm.

In accordance with the invention, armor plates are prepared which can be manufactured in a simple manner. For example, structural wood materials can be utilized for the manufacturing process. Before or after pyrolysis and prior to the ceramicization process, crack stoppers are produced in the armor plate preform and the armor plate is thereby subdivided into functional segments. Due to the functional segments, spatial delimitation of the damage zone can be achieved in the event of an impact, for example, the impact of a projectile on the armor plate.

The armor plate itself is manufactured integrally with the crack stoppers; and relatively large plates can thereby be manufactured and used. The plates can also be manufactured with curvatures so as to be better matched to the field of application. The crack stoppers can be produced in the armor plate preform in a simple manner prior to the ceramicization process, for example, by machining the material and/or laser working. The functional segments can thus be manufactured with defined dimensions. The particular spacings are, for example, selected in such a way that the so-called three-hit condition is fulfilled.

The armor plates in accordance with the invention can be integrated into an armor system as is schematically depicted in FIG. 8 wherein it bears the general reference 68. Such an armor system is described in DE 697 07 560 T2 (EP 0 810 415 B1), which is expressly incorporated by reference herein. At least one ceramic armor plate in accordance with the invention 72 is seated on a structural supporting layer 70 (backing). The structural supporting layer 70 can be made of aluminium or from composite materials such as carbon Kevlar for example. The (at least one) armor plate 72 is adhered to the structural supporting layer 70 by means of an adhesive layer 74 for example. Provision may also be made for a shattering layer 76 upon which the structural supporting layer 70 is arranged. The shattering layer 76 serves to minimize shattering of the structural supporting layer. 70. The armor plate 72 cana be covered by a plurality of covering layers 78, 80, 82. The armor system 68 is bounded at the top by a steel plate 84. In regard to the construction thereof, reference is made to EP 0 810 415 B1. The same construction as described therein can be used, whereby the at least one armor plate in accordance with the invention is utilized instead of a plurality of tiles.

Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing description. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.