METHOD FOR MANUFACTURING AN ELASTIC CERAMIC MATRIX COMPOSITE

Abstract

Disclosed are: damage-resistant ECMCs that need to work and remain elastic between minus 120° C. and positive 300° C.; ECMCs that need to be able to contain a flame of 1900° C. for more than 90 minutes; and composite structures, especially highly stressed structures. One of the characteristic problems of ceramic matrices is their fragility. Indeed, when a fracture starts, it propagates easily in the matrix. Disclosed are elastic ceramic matrix composites (ECMCs), for which: the ceramic matrix is split into solid “ceramic microdomains” (CMDs); the CMDs are connected to one another by a dense network of “elastic microelements” (EMEs); and the bonds between the EMEs and the CMDs are strong chemical bonds, preferably covalent.

Claims

1. A production method of a ceramic composite with an elastic matrix, the method comprises the following steps: Step 1: an admixture comprising at least one of the following elements is dispersed in water an alkali an acid, to obtain “an adjuvant in aqueous solution”, Step 2: then, in the said adjuvant in aqueous solution, an additive is reacted to obtain a “mineral hardener” Step 3: Finally we prepare a “mineral resin powder” Step 4: said mineral hardener is poured and intimately mixed into said mineral resin powder to form a “ceramic mixture” the said process is characterized by the fact that the following steps that can be performed, either following or before some of the preceding steps, are added: Step 5: the preparation of a “fluid silicone homopolymer with active terminations” is carried out, Step 6: during this step, the dispersion of a homopolymer of fluid silicone with active terminations, is realized, either after step 3 or after step 4 to obtain said “elastic ceramic mixture”

2. The method according to claim 1, further comprising: Step 7, consisting in impregnating said “elastic ceramic mixture” obtained at the end of step 6, with means of “fibrous reinforcements”, we then obtain a “ceramic composite with elastic matrix”

3. The method according to claim 2, further comprising an additional step 8, of dispersing, in the mixture, a micro reinforcement network consisting of “dendritic nanofractals”.

4. The method according to claim 3, wherein: “dendritic nanofractals” have so-called nanopatatoid forms (16) of 10 to 50 nanometers in diameter aggregated together by covalent bonds to thereby form dendrites (13, 15), circumscribed in a patatoid volume of 50 to 1000 nanometers in diameter, (the values of the surface of said dendritic nanofractals being included in a range of values whose lower limit is approximately 10 square meters per gram and whose limit higher, is about 750 square meters per gram (measured according to the BET)

5. The method according to claim 3, wherein the dendritic nanofractals are formed based on a combination of at least one of the following products: Metal oxides, not functionalized Metal oxides, functionalized Metalloid oxide, functionalized Metalloid oxide, unfunctionalized Nonmetals, not functionalized.

6. The method according to claim 1 wherein: —said alkali is constituted by a combination and at least one of the following bases: KOH=potassium hydroxide, NaOH=sodium hydroxide, CsOH=cesium hydroxide, LiOH=lithium hydroxide and the said acid being constituted by minus one of the following acids: HCl=hydrochloric acid, H2SO4=sulfuric acid, HF=hydrofluoric acid, H.sub.3PO.sub.4=phosphoric acid, to obtain an “adjuvant in aqueous solution” said additive is constituted by at least one of the following elements: an oxide (silicon, aluminum, magnesium, zirconium, calcium), a metal (aluminum, magnesium, zirconium, of calcium) a metalloid (of silicon), to obtain a “mineral hardener” said mineral resin powder consists of at least one of the following elements: a mineral polymer [consisting of a poly(sialate), (Si/Ai ratio=1)], a mineral polymer [consisting of a poly (sialate-siloxo), (Si/Ai ratio=2)], a polymer mineral [consisting of an aluminosilicate, poly(sialate-disiloxo), (Si/Ai ratio=3) namely (—Si—O—Al—O—).sub.n such as metakaolin (Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n; A mineral polymer [consisting of an aluminosilicate, poly(sialate-disiloxo), namely (—Si—O—Al—O—).sub.n such as metakaolin Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n supplemented with aluminum phosphate (AlPO.sub.4); a complex mineral polymer [consisting of a poly(sialate-disiloxo) aluminosilicate, (Si/Ai ratio=3) namely (—Si—O—Al—O—).sub.n such as metakaolin (Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n and of a micronized alumina namely (Al.sub.2O.sub.3)]; A complex mineral polymer [consisting of a poly(sialate-disiloxo) aluminosilicate, (Si/Ai ratio=3) namely (—Si—O—Al—O—).sub.n such as metakaolin (Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n and d a micronized zirconium oxide, namely. (ZrO.sub.2)]; a complex mineral polymer [consisting of a poly(sialate-disiloxo) aluminosilicate, (Si/Ai ratio=3) namely (—Si—O—Al—O—).sub.n such as metakaolin (Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n of micronized magnesium oxide namely (MgO)]; a complex mineral polymer [consisting of a poly(sialate-disiloxo) aluminosilicate, (Si/Al ratio=3) namely (—Si—O—Al—O—).sub.n such as metakaolin (Si.sub.2O.sub.5,Al.sub.2O.sub.2).sub.n of a micronized calcium oxide namely (CaO)] said active-terminated liquid silicone homopolymer of step 6 consists of at least one of the following terminations: OH-terminus, H-terminus, H-terminal hybrid on one side and OH on the other, termination alcohol (methanol), alcohol (ethanol) terminus, to obtain said “flexible ceramic mixture”.

7. The method according to claim 3, wherein the “fibrous reinforcements” are chosen from at least one of the following functionalized fibers: *Bore fibers. *Silica functionalized. *Quartz functionalized. *Basalt preferentially functionalized. *Functionalized glass. *Carbon not functionalized. *Silicon carbide not functionalized. *Functionalized ceramics (eg alumina, alumina mullite). *Non-functionalized zirconium. *Stainless steel functionalized. * Inconel not functionalized. *Functionalized polysilazane. *Aramid, non-functionalized. *Polyethylene HD (Example DYNEEMA).

8. The method according to claim 1, further comprising an additional step 8, of dispersing, in the mixture, a micro reinforcement network consisting of “dendritic nanofractals”.

9. The method of claim 5, wherein the dendritic nanofractals are formed based on a combination comprising a functionalized metal oxide selected from a group consisting of titanium oxide and zirconium oxide.

10. The method of claim 5, wherein the dendritic nanofractals are formed based on a combination comprising a functionalized metal oxide in the form of alumina.

11. The method of claim 5, wherein the dendritic nanofractals are formed based on a combination comprising a functionalized metalloid oxide selected from a group consisting of silicon oxide, boron oxide, and boric anhydride.

12. The method of claim 5, wherein the dendritic nanofractals are formed based on a combination comprising a unfunctionalized metalloid oxide in the form of silicon carbide.

13. The method according to claim 3, wherein the dendritic nanofractals are formed based on a combination of at least one of the following products: Metal oxides, not functionalized Metal oxides, functionalized Metalloid oxide, functionalized Metalloid oxide, unfunctionalized Nonmetals, not functionalized.

14. The method according to claim 3, wherein the dendritic nanofractals are formed based on a combination of at least one of the following products: a metal oxides, selected from the group consisting of TiO.sub.2 titanium oxide and ZrO.sub.2 zirconium oxide, not functionalized; alumina Al2O3, functionalized; a metalloid oxide, selected from the group consisting of silicon oxide, boron oxide, and boric anhydride, functionalized; SiC silicon carbide, unfunctionalized; and a nonmetal, selected from the group consisting of phosphorus oxide, phosphoric anhydride (P.sub.2O.sub.5), and carbon black, not functionalized.

15. The method according to claim 4, wherein the dendritic nanofractals are formed based on a combination of at least one of the following products: a metal oxides, selected from the group consisting of TiO.sub.2 titanium oxide and ZrO.sub.2 zirconium oxide, not functionalized; alumina Al2O3, functionalized; a metalloid oxide, selected from the group consisting of silicon oxide, boron oxide, and boric anhydride, functionalized; SiC silicon carbide, unfunctionalized; and a nonmetal, selected from the group consisting of phosphorus oxide, phosphoric anhydride (P.sub.2O.sub.5), and carbon black, not functionalized.

Description

DESCRIPTION OF THE FIGURES

[0105] FIG. 1 is a chemical representation of an example of homopolymers of fluid silicone with active terminations (1) also called “elastic microelement” (EME). (In the example shown, it is an OH termination), where n is the number of iterations of the base module.

[0106] FIG. 2 is a spatial representation of an example of homopolymers of fluid silicone with active terminations (1) also called “elastic microelement” (EME).

[0107] FIG. 3 spatial representation of an example of solid “micro ceramic domains” (MCD) (2)

[0108] FIG. 4 spatial representation of an example of solid “micro ceramic domains” (MCD) (2) interconnected three-dimensionally by a dense network of “micro elastic elements” (EME) (1). This set constitutes an “elastic ceramic matrix” (ECM). It suffices to add to this matrix a network macro and preferentially a micro reinforcement network to result in an “elastic ceramic matrix composite” (ECMC)

[0109] FIG. 5 shows an example of polymerization=polycrystallization of a solid “ceramic micro-domain” (CMD) (2). Water (5) is used in which, for example, caustic soda (6) is dissolved in order to obtain a pH 11. The silica dispersed in this water is then converted into silicate (4). The liquid thus obtained is mixed with metakaolin (3). This gives a slip. During the polycrystallization, oxide ceramic crystals are obtained (2).

[0110] An alkaline solution is a solution of water in which we dissolved an alcaly such as: sodium hydroxide, or caustic soda (NaOH). *sodium carbonate (Na.sub.2CO.sub.3). *Potassium hydroxide, or caustic potash (KOH). *The K+ cation is less soluble in water than the Na+ cation. In addition, it is more difficult to complex, and can be more easily retained by compounds, such as clays. It is therefore more interesting in our applications.

[0111] Radical type vulcanization, of the fluid silicone homopolymer, can be carried out in a few minutes at temperatures above 110° C., using one or more organic peroxides (benzoyl peroxide and dicumyl peroxide for simplest cases) in low proportion (1 to 2%).

[0112] It is possible to cure with an organotannous catalyst (dibutyltin dilaurate), (nC.sub.4H.sub.9).sub.2Sn(OOCC.sub.11H.sub.23).sub.2), this reaction can be accelerated by the addition of a platinium salt.