Particulate composite ceramic material, part comprising said material, and method for the preparation of said part

Patent metadata

Field	Value
Publication number	US-12037292-B2
Application number	US-201816766991-A
Country	US
Kind code	B2
Filing date	Nov 27, 2018
Priority date	Nov 29, 2017
Publication date	Jul 16, 2024
Grant date	Jul 16, 2024

Abstract

A particulate composite ceramic material may include: particles of at least one first ultra-high-temperature ceramic “UHTC,” the outer surface of the particles being at least partially covered by a porous layer made of at least one second UHTC in amorphous form; and the particles defining a space therebetween; optionally, porous clusters of the at least one second ultra-high-temperature ceramic in amorphous form, distributed in said space; a dense matrix and at least one third UHTC in crystallized form at least partially filling the space; optionally, a dense coating made of at least the third UHTC in crystallized form, covering the outer surface of the matrix, the matrix and the coating representing 5% to 90% by mass with respect to the total mass of the material. A part may include such a particulate ceramic composite material.

First claim

The invention claimed is:

1. A particulate composite ceramic material, comprising:
particles comprising a first ultra-high-temperature ceramic in crystallized form, an outer surface of the particles being at least partially covered by a porous layer comprising a second ultra-high-temperature ceramic in amorphous form, the first ultra-high-temperature ceramic being present in a range of from 25 to 90 mass %, and the second ultra-high-temperature ceramic being present in a range of from 2 to 15 mass %, each with respect to total particulate composite ceramic material mass, and the particles defining a space therebetween;
optionally, porous clusters of the second ultra-high-temperature ceramic in amorphous form, distributed in the space;
a dense matrix comprising a third ultra-high-temperature ceramic in crystallized form at least partially filling the space;
optionally, a dense coating comprising the third ultra-high-temperature ceramic in crystallized form, covering the outer surface of the dense matrix,
wherein the dense matrix and, optionally further the dense coating, are present in a range of from 5 to 90 mass %, with respect to the total particulate composite ceramic material mass,
wherein the porosity of the porous layer is in a range of from 15 to 30%,
wherein the first, second, and third ultra-high-temperature ceramics comprise a boride, carbide, nitride, silicide, and/or carbon.

2. The material of claim 1 , having an overall porosity greater than or equal to 5%.

3. The material of claim 1 , wherein the porous layer has a thickness of 0.1 to 1 micron.

4. The material of claim 1 , wherein the first, second, and third ultra-high-temperature ceramics independently consist of one or more boride ceramics, carbide ceramics, nitride ceramics, silicide ceramics, carbon, or mixtures thereof.

5. The material of claim 4 , wherein the first, second, and ultra-high-temperature third ceramics are independently selected from the group consisting of SiC, MoSi 2 , TiC, TaC, ZrC, ZrB 2 , HfC, HfB 2 , BN, AlN, TiN, carbon, and mixtures thereof.

6. The material of claim 1 , wherein the first, second, and third ultra-high-temperature ceramics are identical.

7. The material of claim 6 , wherein the first, second, and third ultra-high-temperature ceramics are SiC.

8. The material of claim 7 , wherein the first ultra-high-temperature ceramic is SiC in a crystallized form,
wherein the second ceramic is amorphous porous SiC, and
wherein the third ceramic is SiC in β crystallized form.

9. The material of claim 1 , which is formed using temperatures less than 1600° C.

10. The material of claim 1 , wherein the third ultra-high-temperature ceramic is deposited by chemical vapor infiltration.

11. The material of claim 1 , having a maximum residual porosity of 20%.

12. A part, comprising:
the particulate composite ceramic material of claim 1 .

13. The part of claim 12 , which is at least part of a heat exchanger, of a catalyst support, of a filter operating in a corrosive atmosphere and/or at a high temperature, of a furnace part or of a furnace, of a heating resistor, of a combustion chamber, of a varistor, of a substrate suitable for a power component, of a shielding, of a rolling component, or of an abrasive coating.

14. A method for manufacturing the part of claim 12 , the method comprising:
(a) preparing a raw or green part, comprising a mixture of a powder of particles of the first ultra-high-temperature ceramic and of a powder of particles of a refractory pore-forming material capable of being eliminated by a chemical attack, a precursor polymer of the second ultra-high-temperature ceramic, and a solvent of the precursor polymer;
(b) evaporating the solvent and crosslinking the precursor polymer of the second ultra-high-temperature ceramic;
(c) performing a heat treatment to transform the precursor polymer into the second ultra-high-temperature ceramic, which is in the form of a porous layer that at least partially covers the outer surface of the particles of the first ultra-high-temperature ceramic, and optionally of porous clusters;
(d) eliminating the refractory pore-forming material by a chemical attack, whereby a part is obtained comprising the particles of the first ultra-high-temperature ceramic, the second ultra-high-temperature ceramic in porous form as a porous layer that at least partially covers the outer surface of the particles and optionally of porous clusters, and an internal porosity between the particles;
(e) treating the part obtained at the end of the eliminating (d) by a chemical vapor infiltration technique in order to deposit the third ultra-high-temperature ceramic in the internal porosity of the part; and
(f) optionally, depositing the third ultra-high-temperature ceramic on the outer surface of the part obtained at the end of the treating (e) by a chemical vapor deposition technique.

15. The method of claim 14 , wherein the preparing (a) comprises:
preparing the mixture of a powder of particles of the first ultra-high-temperature ceramic and of a powder of particles of the refractory pore-forming material capable of being eliminated by a chemical attack; and
forming, shaping the mixture of a powder of particles of the first ultra-high-temperature ceramic, and of a powder of particles of the refractory pore-forming material capable of being eliminated by a chemical attack, in the form shape, of the raw or green part.

16. The method of claim 14 , wherein the refractory pore-forming material is capable of withstanding a temperature greater than 300° C.

17. The method if claim 16 , wherein the refractory pore-forming material comprises plaster, potassium carbonate, calcium carbonate, or potassium sulfate.

18. The method of claim 14 , wherein preparation of the mixture of the powder of particles of the first ultra-high-temperature ceramic, and of the powder of particles of the refractory pore-forming material is carried out by a dry process or by a wet process.

19. The method of claim 14 , wherein forming, shaping of the mixture of a powder of particles of the first ultra-high-temperature ceramic, and of a powder of particles of the refractory pore-forming material is carried out by molding, by slip casting, with a filter press, or by an addictive manufacturing technique.

20. The method of claim 14 , wherein the precursor polymer of the second ceramic, is added
during preparing the mixture of the powder of particles of the first ultra-high-temperature ceramic, and of the powder of the refractory pore-forming material; or
during forming and/or shaping the mixture of a powder of particles of the first ultra high-temperature ceramic, and of a powder of particles of the refractory pore-forming material; or after the forming and/or shaping.

21. The method of claim 14 , wherein the precursor polymer, which is a pre-ceramic polymer, of the second ultra-high-temperature ceramic comprises a polycarbosilane, polysilazane, and/or polyborosilane.

22. The method of claim 14 , wherein the evaporating (b) and the performing (c) are grouped.

23. The method of claim 14 , wherein during the performing (c) the heat treatment is carried out at a temperature in a range of from 600° C. to 1600° C.

24. The method of claim 14 , wherein, during the eliminating (d), the chemical attack is performed with a solution comprising an acid.

Assignees

• Commissariat Energie Atomique

Inventors

• David Patrick
• Piquero Thierry
• Martegoutte Julien
• Schuster Frederic

Classifications

• Y10T428/2993

  Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.] · CPC title

• C04B2235/9607

  Thermal properties, e.g. thermal expansion coefficient · CPC title

• C04B2235/85

  Intergranular or grain boundary phases · CPC title

• C04B2235/614

  Gas infiltration of green bodies or pre-forms · CPC title

• C04B2235/6026

  Computer aided shaping, e.g. rapid prototyping · CPC title