A shaped composite ceramic for armor applications and its process thereof

Abstract

The present disclosure relates to a shaped composite ceramic product specifically designed for armor applications. This product comprises a formulation of alpha silicon carbide, alumina, silicon nitride, and silicon oxynitride. The alpha silicon carbide is present in amounts ranging from 55 to 75 wt% and is characterized by two distinct mean grain sizes: 80 to 180 microns and 0.1 to 10 microns. Additionally, a manufacturing process for producing the shaped composite ceramic product is also provided. The in-situ formation of silicon nitride and silicon oxynitride during processing further enhances the mechanical properties of the final product, contributing to improved performance in protective applications.

Description

[0001] A SHAPED COMPOSITE CERAMIC FOR ARMOR APPLICATIONS AND ITS

[0002] PROCESS THEREOF

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to the field of ceramic materials, specifically to advancements in armor materials. In particular, the invention relates to a novel composite ceramic material comprising reaction-bonded silicon nitride and silicon oxynitride integrated within an alpha silicon carbide (SiC) and alumina matrix, and a process thereof.

[0005] BACKGROUND OF THE INVENTION

[0006] The growing demand for advanced armor materials in ballistic and industrial sectors has driven significant research and development in composite ceramics. While traditional ceramic armor solutions are effective in certain situations, they often face limitations such as brittleness, high density, and insufficient mechanical properties. Additionally, specialized applications, such as personal body armor, require ceramics with superior ballistic resistance, reduced weight, and enhanced thermal resistance.

[0007] Currently, alumina and steel are widely used in vehicle armor applications. However, the need to reduce armor system weight has increased due to their high density and relatively low hardness for high-performance use. Silicon carbide, known for its exceptional hardness, toughness, and thermal resistance, is an outstanding choice for both personal and vehicle armor. Despite challenges such as high cost, manufacturing complexities, porosity, and grain size uniformity, silicon carbide remains a strong candidate for advanced armor materials.

[0008] Advanced processes like reaction-bonded silicon carbide, which involves infiltrating a silicon carbide preform with molten silicon, and reaction-bonded silicon nitride, where silicon powder reacts with nitrogen at high temperatures, have been developed to improve toughness and durability in ceramic armor. However, these methods face challenges, including porosity, oxidation resistance, and high manufacturing costs. Similarly, in-situ formation processes offer promise but remain complex and expensive.

[0009] Traditional methods, such as those disclosed in US7803732B1 and US5618768A, use hot pressing and hot isostatic pressing (HIP) for densification of advanced composites like SiC- ZrCh and SiC-SisN^ While these techniques offer excellent high-temperature strength and density, they are time-consuming, costly, and require high processing temperatures over 2000°C, posing scalability challenges.

[0010] Despite these advancements in the prior art, there are also drawbacks, such as lower hardness and strength, high costs, manufacturing complexities, and issues with scalability and porosity. To address these limitations, there is a need for a novel composite material for armor components that offers significantly enhanced mechanical properties, including greater hardness and fracture toughness, while also demonstrating lower density and porosity compared to traditional ceramic armor solutions.

[0011] Therefore, the present invention addresses these drawbacks by developing a novel composite material through an innovative reaction-bonding process that enhances mechanical properties, offering superior protection, weight reduction, and improved efficiency.

[0012] OBJECTS OF THE INVENTION

[0013] The present invention addresses these challenges by introducing a shaped composite ceramic product specifically designed for armor applications.

[0014] Therefore, the primary object of the present invention is to provide a high-performance shaped composite ceramic product for armor applications.

[0015] The main object of the present invention is to provide a composite ceramic product for armor applications, offering exceptional protection and durability.

[0016] Another object of the present invention is to provide a shaped composite ceramic product that offers enhanced mechanical strength, impact resistance, and thermal stability.

[0017] Yet another object of the present invention is to provide a ceramic product with a designed shape that facilitates the straightforward replacement of damaged sections of armor plates.

[0018] Further, another object of the present invention is to provide a process for preparing the shaped composite ceramic product that is efficient and cost-effective. SUMMARY OF THE INVENTION

[0019] According to a first aspect of the invention, a shaped composite ceramic product specifically designed for enhanced armor applications is provided. This ceramic product offers superior protection and durability through its unique composition and manufacturing process.

[0020] The shaped ceramic product comprises alpha silicon carbide in an amount ranging from 55 to 75 wt%, characterized by having two distinct mean grain sizes: i) between 80 and 180 microns and ii) between 0.1 and 10 microns. Additionally, it contains alumina in an amount ranging from 0.5 to 5 wt%, silicon nitride in an amount ranging from 25 to 40 wt%, and silicon oxynitride in an amount ranging from 1 to 10 wt%, with silicon nitride and silicon oxynitride formed in situ within the matrix.

[0021] The present invention also encompasses the ceramic product as an antiballistic plate or a component of an antiballistic plate, with the shape of the ceramic component including, but not limited to, hexagonal, square, triangular, and rectangular forms. These shapes can be utilized as easily replaceable components in antiballistic plates. This versatility of the shaped components allows for the easy replacement of damaged sections of armor plates, thereby extending their service life and maintaining the protective integrity of armor systems.

[0022] Another aspect of the present invention provides a method for manufacturing a shaped composite ceramic product. This method involves granulating raw materials, including 55 to 85 wt% silicon carbide, 0.5 to 5 wt% alumina, 15 to 25 wt% silicon and optional additives to create a uniform mixture. The granulated mixture is then press-fabricated into a preform shape using a hydraulic press, ensuring uniform compaction. The preform is subsequently heated in a nitrogen atmosphere at temperatures between 1350 and 1550°C, with 1450°C being optimal. This heating process facilitates the in-situ formation of silicon nitride and silicon oxynitride, resulting in a dense and robust ceramic matrix.

[0023] Moreover, the manufacturing process for the composite ceramic product is designed to be efficient and scalable. By granulating the raw materials, forming a preform shape, and heating it in a nitrogen atmosphere, the process ensures optimal bonding and structural integrity.

[0024] The shaped composite ceramic product of the present invention enhances existing armor materials by incorporating a unique combination of alpha silicon carbide, alumina, silicon nitride, and silicon oxynitride, with varying grain sizes and the in-situ formation of silicon nitride and silicon oxynitride within the ceramic matrix. This innovative composition improves hardness, fracture toughness, and overall strength while reducing density and porosity, resulting in a lightweight yet robust material that offers exceptional durability and effectiveness in protective applications.

[0025] The manufacturing process is designed to include alumina in the raw materials to enhance structural integrity while maintaining cost-effectiveness. This contributes to an economical production process, light weight advantage and maintaining the performance of the final ceramic product.

[0026] The shaped design facilitates the easy integration of new ceramic sections into existing armor plates, allowing for localized replacement of damaged areas without the need to replace the entire panel, thus improving cost-effectiveness and maintaining functionality.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention can be better understood, and its numerous features and advantages made apparent to those skilled in the art by referencing the accompanying drawings.

[0029] The use of the same reference symbols in different drawings indicates similar or identical items.

[0030] FIG. 1 illustrates a perspective view of a hexagonally shaped ceramic material, according to one or more embodiments.

[0031] FIG. 2 illustrates a front view of a plate formed from interlocking hexagonally shaped ceramic materials, according to one or more embodiments.

[0032] Skilled artisans appreciate that elements in the drawings are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the disclosure. DETAILED DESCRIPTION

[0033] The following description, in combination with the figures, is provided to assist in understanding the teachings disclosed herein. The following discussion will focus on specific implementations and embodiments of the teachings. This discussion is provided to assist in describing the teachings and should not be interpreted as a limitation on the scope or applicability of the teachings.

[0034] Note that not all of the activities described in the general description, or the examples are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed is not necessarily the order in which they are performed.

[0035] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that comprises a list of features is not necessarily limited only to those features but may include other features not expressly listed or inherent to such method, article, or apparatus. Further, unless expressly stated to the contrary, "or" refers to an inclusive- or and not to an exclusive-or.

[0036] The use of "a" or "an" is employed to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. This description should be read to include one or at least one and the singular also includes the plural, or vice versa, unless it is clear that it is meant otherwise.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent that certain details regarding specific materials and processing acts are not described, such details may include conventional approaches, which may be found in reference books and other sources within the manufacturing arts.

[0038] Reference throughout this specification to “one embodiment” “an embodiment” “some embodiments” “alternate embodiment” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of such phrases throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0039] The term ‘B / L ratio’, as used herein, refers to the breadth-to-length ratio of the grains, where 'breadth' (B) refers to the width (or diameter) and 'length' (L) refers to the longest dimension of the grains. For spherical grains, the B / L ratio would be close to 1, as the breadth and length are essentially equal in a perfect sphere.

[0040] The main aspect of the present invention is to provide a shaped composite ceramic product for armor applications comprising silicon carbide, alumina, silicon nitride and silicon oxynitride. Said ceramic product is specifically designed to offer superior protection and durability.

[0041] In an embodiment of the present disclosure, the silicon carbide is alpha silicon carbide and is characterized by having two distinct mean grain sizes: one ranging between 80 and 180 microns and another between 0.1 and 10 microns. The combination of these grain sizes enhances the mechanical strength and impact resistance of the ceramic product.

[0042] In an embodiment of the present disclosure, the silicon carbide present in the said ceramic product in an amount ranging from 55 to 75 wt%.

[0043] In an embodiment of the present disclosure, the alumina present in the said ceramic product in an amount ranging from 0.5 to 5 wt%.

[0044] In an embodiment of the present disclosure, the ceramic product contains silicon nitride in an amount ranging from 25 to 40 wt%. Silicon nitride contributes to the ceramic's toughness and thermal stability and is formed in situ during the manufacturing process, meaning it is generated within the matrix rather than being added as a separate component.

[0045] In an embodiment of the present disclosure, the silicon oxynitride present in the ceramic product comprises silicon oxynitride in an amount ranging from 1 to 10 wt%, which is also formed in situ. This component further enhances the ceramic matrix, improving its overall performance in armor applications by increasing structural integrity and resistance to ballistic impacts. In a preferred embodiment of the present disclosure, the silicon nitride comprises alpha silicon nitride in an amount ranging from 1 to 5 wt%.

[0046] In a preferred embodiment of the present disclosure, the silicon nitride comprises alpha silicon nitride in an amount ranging from 0.1 to 3 wt%.

[0047] In a preferred embodiment of the present disclosure, the silicon nitride comprises beta silicon nitride in an amount ranging from 24 to 35 wt%.

[0048] In a preferred embodiment of the present disclosure, the silicon nitride comprises beta silicon nitride in an amount ranging from 20 to 30 wt%.

[0049] In an embodiment of the present disclosure, the ceramic product optionally contains boron carbide.

[0050] In an embodiment of the present disclosure, the ceramic product optionally contains Titanium Carbide Nitride (TiCxNl-x) in a crystalline phase in an amount ranging from 0 to 5 wt%.

[0051] In addition to the primary components, the silicon nitride in the ceramic product includes alpha silicon nitride in an amount ranging from 1 to 5 wt%. This specific type of silicon nitride enhances the material's hardness and overall mechanical strength, contributing to its effectiveness as an armor material.

[0052] The silicon nitride component also contains beta silicon nitride in an amount ranging from 20 to 35 wt%. The presence of beta silicon nitride improves the toughness of the ceramic product, making it more resistant to high-impact forces and enhancing its performance in armor applications.

[0053] In an embodiment of the present disclosure, the ceramic product is an antiballistic plate or a component of an antiballistic plate.

[0054] In an embodiment of the present disclosure, the shape of the ceramic component is including, but not limited to hexagonal, square, triangular, and rectangular. In a specific embodiment of the present disclosure, the shape of the ceramic component is hexagonal.

[0055] In an embodiment of the present disclosure, the desired shape or the configuration of the ceramic material allows for easy replacement of the damaged section of the armor plate.

[0056] In a specific embodiment of the present disclosure, the ceramic product is a component of an antiballistic plate.

[0057] The ceramic product described is ideally suited for use as a component of an antiballistic plate. The robust properties imparted by the silicon carbide, silicon nitride, and silicon oxynitride make it effective in absorbing and dispersing impact energy, thereby enhancing the protective capabilities of the armor plate.

[0058] FIG. 2 illustrates a front view of an armor plate uniquely formed from interlocking hexagonally shaped ceramic materials, as described in the present invention. This design enhances the structural integrity of the plate and optimizes its performance in ballistic applications. Additionally, the specific shape of the ceramic material allows for easy replacement of any damaged portions of the armor plate.

[0059] A process is provided for preparing a shaped composite ceramic product comprising granulating raw materials to form a uniform mixture, press fabricating the granulated mixture into a preform shape; and heating the preform in a nitrogen atmosphere to facilitate the in-situ formation of silicon nitride (SislSU) and silicon oxynitride within the matrix, resulting in a dense and robust material with desired shape.

[0060] Said process begins by granulating raw material into fine particles. These raw materials are carefully blended with optional additives to form a uniform mixture with controlled grain sizes, ensuring consistency throughout the ceramic matrix. The granulated mixture is press fabricated into a preform shape using a suitable molding or pressing technique. This step is crucial in defining the initial geometry of the composite product and ensures the material is compacted into a dense form that can withstand further processing. The pressing process may involve techniques such as uniaxial or isostatic pressing, depending on the desired shape and uniformity. Once the preform shape is established, it is subjected to heating in a nitrogen atmosphere at a controlled temperature. The heating process is designed to facilitate the in-situ formation of silicon nitride (SisN^ and silicon oxynitride within the matrix. The nitrogen environment is critical, as it promotes the chemical reactions between silicon carbide and nitrogen to form silicon nitride and silicon oxynitride and Titanium Carbide Nitride. These nitride phases are formed directly within the ceramic matrix, enhancing the material’s overall mechanical properties, such as hardness, fracture toughness, and high-temperature resistance.

[0061] The temperature and duration of the heating step are carefully controlled to optimize the formation of the silicon nitride and oxynitride phases, ensuring that they are homogeneously distributed within the composite structure. This results in a dense, robust material with minimal porosity, increased strength, and improved performance in demanding applications.

[0062] After heating, the shaped preform optionally undergoes a cooling phase, where it is slowly cooled to room temperature to prevent thermal shock and ensure dimensional stability. The resulting composite ceramic product has the desired shape, improved mechanical properties, and is ready for use in applications such as armor materials, where its strength, durability, and lightweight nature are essential.

[0063] In one embodiment of the present disclosure, the raw material in the said process comprises 55 to 85 wt% silicon carbide (SiC), 0.5 to 5 wt% alumina (AI2O3), and 15 to 25 wt% silicon and other optional additives.

[0064] In a preferred embodiment of the present disclosure, the silicon carbide in the raw material has two distinct mean grain sizes one is between 80 and 180 microns, and another is between 0.1 and 10 microns.

[0065] In a preferred embodiment of the present disclosure, the silicon carbide in the raw material has mean grain size between 80 and 180 microns, comprising an amount ranging from 30 to 45 wt%.

[0066] In a preferred embodiment of the present disclosure, the silicon carbide in the raw material has mean grain size between 1 and 10 microns, comprising an amount ranging from 25 to 40 wt%. In a preferred embodiment of the present disclosure, the silicon carbide particles in the raw material have B / L ratio ranging from 0.6 to 1.

[0067] In a preferred embodiment of the present disclosure, the alumina in the raw material has mean grain size ranging from 1 to 10 microns.

[0068] In a preferred embodiment of the present disclosure, the silicon in the raw material has mean grain size ranging from 20 to 70 microns.

[0069] In an embodiment of the present disclosure, the raw material optionally comprises a sintering additive selected from the group comprising carbon, carbides of boron, titanium, zirconium or zirconium borides, oxides of titanium, either alone or in mixture.

[0070] In a specific embodiment of the present disclosure, the raw material optionally comprises boron carbide.

[0071] In an embodiment of the present disclosure, the raw material optionally comprises titanium oxide.

[0072] In an embodiment of the present disclosure, the process optionally includes an iron oxide catalyst for nitridation, enabling the in-situ formation of silicon nitride and silicon oxynitride.

[0073] In a preferred embodiment of the present disclosure, the process involves heating the preform at a temperature ranging from 1350 to 1550°C.

[0074] In a specific embodiment of the present disclosure, the process involves heating the preform at 1450°C.

[0075] In a preferred embodiment of the present disclosure, the process involves press fabricating the granulated mixture into the preform shape by using hydraulic press. In a preferred embodiment of the present disclosure, the raw material comprises alpha silicon carbide with a desired B / L ratio, which improves hardness, strength, and high-temperature resistance.

[0076] The shaped composite ceramic product is manufactured in various geometric forms, including hexagonal, square, triangular, and rectangular shapes. This versatility in shape selection allows for customization to meet specific design requirements and optimize the fit and coverage of armor systems.

[0077] The ceramic product may optionally include boron carbide. The addition of boron carbide can significantly increase the hardness and ballistic resistance of the composite ceramic, providing enhanced protection against projectiles.

[0078] The silicon carbide used in the process has two distinct mean grain sizes: between 80 and 180 microns and between 0.1 and 10 microns. This dual-grain-size approach optimizes the material’s mechanical properties by balancing the coarse and fine particles to enhance strength and impact resistance.

[0079] The silicon carbide with a mean grain size between 80 and 180 microns is used in amounts ranging from 30 to 45 wt%. This distribution ensures the material's durability and mechanical performance by providing a robust structure capable of withstanding high-impact forces.

[0080] Silicon carbide with a mean grain size between 1 and 10 microns is used in amounts ranging from 25 to 40 wt%. These fine particles contribute to the material's density and improve its overall strength and stability.

[0081] The process utilizes silicon carbide with a B / L ratio ranging from 0.6 to 1. This ratio is crucial for achieving the desired bonding and mechanical properties of the ceramic product, ensuring effective integration and performance.

[0082] Alumina used in the process has a mean grain size ranging from 1 to 10 microns. This specification ensures that alumina contributes effectively to the material's structural integrity and overall performance. Silicon used in the raw materials has a mean grain size ranging from 20 to 70 microns. This grain size range facilitates the effective formation of silicon nitride and silicon oxynitride during the heating process.

[0083] The heating of the preform occurs at temperatures ranging from 1350 to 1550°C. This temperature range is critical for achieving the desired chemical reactions and properties of the final ceramic product.

[0084] A specific heating temperature of 1450°C is used to optimize the formation of silicon nitride and silicon oxynitride, resulting in a high-quality ceramic material.

[0085] The press-fabrication of the granulated mixture into the preform shape is conducted using a hydraulic press. This method ensures uniform compaction and shaping, contributing to the final product's consistency and quality.

[0086] Alpha silicon carbide with the desired B / L ratio provides superior hardness, strength, and high- temperature resistance, enhancing the overall performance of the ceramic product.

[0087] The inclusion of alumina in the raw materials contributes to the cost-effectiveness of the process while providing additional structural integrity to the final ceramic product. This makes the manufacturing process more economical without compromising performance.

[0088] Overall, the invention provides advancements in the field of ceramic armor materials by combining tailored material compositions and shapes to meet the rigorous demands of modern armor applications.

[0089] EXAMPLES

[0090] Example 1

[0091] Preparation of a composite ceramic materials

[0092] All the constituent powders of the raw materials listed in Table 1 were combined using a ball mill, with 12 wt.% water added to create a homogeneous slip. The B / L ratio of the silicon carbide raw material was 0.67. The formed slip underwent filtration using a filter press to eliminate excess water and form a filter cake. The filter cake material was further processed through a granulator machine to produce optimized granules. The homogeneous granules were then pressed into the desired shape utilizing a die-punch setup in a hydraulic press. The green compacts were subjected to sintering in a furnace set at 1450°C, resulting in the production of a denser final product in hexagonal shape (FIG. 1 ), achieved in a shorter timeframe.

[0093] Table 1 : Raw material formulation

[0094] The final product obtained from the process was analyzed using X-ray diffraction (XRD), and the chemical composition of the ceramic material is presented in Table 2.

[0095] Table 2: Chemical composition of the shaped composite material

[0096] The chemical analysis of the ceramic material, as detailed in Table 2, indicates that the final product comprises silicon carbide, silicon nitride, and silicon oxynitride phases.

[0097] Resulting Properties

[0098] The press fabrication step, along with the selection and size of raw materials, contributed to the production of armor plates with enhanced density and mechanical strength, distinguishing this approach from existing techniques. The obtained ceramic material exhibited superior Vickers hardness and mechanical properties compared to conventional ceramic armor materials, in general. The specific properties of the ceramic materials are listed in Table 3.

[0099] Table 3

[0100] The resulting ceramic material demonstrated exceptional Vickers hardness and mechanical properties. Table 3 clearly shows that the ceramic product achieved superior projectile velocity (V50 in m / s) and flexural strength (CMOR). These enhancements are attributed to the carefully selected composition and the advanced processing techniques employed, both of which contribute to the improved performance of the armor plates.

[0101] In summary, the unique composition, specialized manufacturing process, and improved properties of the resulting ceramic material distinguish the broadest embodiment of this invention from existing technologies, representing a significant advancement in ceramic armor technology.

[0102] The shaped composite ceramic product, with its unique composition and manufacturing process, represents a significant advancement in armor technology. Its diverse applications across various industries demonstrate its potential to enhance safety and protection against ballistic threats, making it a valuable addition to the field of advanced materials.

[0103] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any feature(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature of any or all the claims.

[0104] The specification and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein. Certain features, that are for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment.

[0105] Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in a sub combination. Further, reference to values stated in ranges includes each and every value within that range. Many other embodiments may be apparent to skilled artisans only after reading this specification. Other embodiments may be used and derived from the disclosure, such that a structural substitution, logical substitution, or another change may be made without departing from the scope of the disclosure. Accordingly, the disclosure is to be regarded as illustrative rather than restrictive. The description in combination with the figures is provided to assist in understanding the teachings disclosed herein, is provided to assist in describing the teachings, and should not be interpreted as a limitation on the scope or applicability of the teachings. However, other teachings can certainly be used in this application.

[0106] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent that certain details regarding specific materials and processing acts are not described, such details may include conventional approaches, which may be found in reference books and other sources within the manufacturing arts.

[0107] While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

Claims

CLAIMS1. A shaped composite ceramic product, comprising:(i) alpha silicon carbide in an amount ranging from 55 to 75 wt%, characterized by having two distinct mean grain sizes: i) between 80 and 180 microns and ii) between 0.1 and 10 microns;(ii) alumina in an amount ranging from 0.5 to 5 wt%;(iii) silicon nitride in an amount ranging from 25 to 40 wt%;(iv) silicon oxynitride in an amount ranging from 1 to 10 wt%; and wherein silicon nitride and silicon oxynitride formed in situ within the matrix.

2. The shaped composite ceramic material as claimed in claim 1, wherein the ceramic product is an antiballistic plate or a component of an antiballistic plate.

3. The shaped composite ceramic product as claimed in claim 2, wherein the shape of the ceramic component is selected from hexagonal, square, triangular, and rectangular.

4. The shaped composite ceramic material as claimed in claim 1, wherein the silicon nitride comprising alpha silicon nitride in an amount ranging from 1 to 5 wt%.

5. The shaped composite ceramic material as claimed in claim 1, wherein the silicon nitride comprising beta silicon nitride in an amount ranging from 24 to 35 wt%.

6. The shaped composite ceramic material as claimed in claim 1, wherein the ceramic product optionally comprises boron carbide.

7. A process for preparing a shaped composite ceramic product, comprising:(i) granulating raw materials comprising 55 to 85 wt% silicon carbide (SiC), 0.5 to 5 wt% alumina (AI2O3), 15 to 25 wt% silicon and optional additives to form a uniform mixture;(ii) press fabricating the granulated mixture into a preform shape; and(iii) heating the preform in a nitrogen atmosphere to facilitate the in-situ formation of silicon nitride (SisN^ and silicon oxynitride within the matrix, resulting in a dense, shaped material.

8. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the silicon carbide having two distinct mean grain sizes: i) between 80 and 180 microns in an amount ranging from 30 to 45 wt% and ii) between 0.1 and 10 microns in an amount ranging from 25 to 40 wt%.

9. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the B / L ratio of the silicon carbide particles is ranging from 0.6 to 1.

10. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the alumina having mean grain size ranging from 1 to 10 microns.

11. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the silicon having mean grain size ranging from 20 to 70 microns.

12. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the raw material optionally comprises boron carbide.

13. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the process optionally includes oxides of iron.

14. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the process optionally includes oxides of titanium.

15. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the heating the preform at temperature ranging from 1350 to 1550°C.

16. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the heating the preform at 1450°C.

17. The process for preparing a shaped composite ceramic product as claimed in claim 7, wherein the press fabricating the granulated mixture into the preform shape by using a uniaxial press.

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