Systems and methods for making ceramic powders and ceramic products

Patent metadata

Field	Value
Publication number	US-11753345-B2
Application number	US-201816228295-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Jun 23, 2016
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

Systems and methods for making ceramic powders are provided. The method for forming a ceramic powder includes: preparing a precursor mixture, wherein the preparing comprises adding at least one additive to a plurality of reagents, wherein the at least one additive includes at least one of: an oxide, a salt, a pure metal, or an alloy of elements ranging from atomic numbers 21 through 30, 39 through 51, and 57 through 77 and combinations thereof; and carbothermically reacting the precursor mixture to form a ceramic powder, wherein, due to the preparing step, the precursor mixture comprises a sufficient amount of the at least one additive to form the ceramic powder, wherein the ceramic powder comprises: (a) a morphology selected from the group consisting of irregular, equiaxed, plate-like, and combinations thereof; and (b) a particle size distribution selected from the group consisting of fine, intermediate, coarse, and combinations thereof.

First claim

We claim:

1. A method, comprising:
(a) preparing a precursor mixture, wherein the preparing comprises adding at least one additive to a plurality of reagents;
(i) wherein the plurality of reagents comprise titanium dioxide, a boron source, and a carbon source;
(ii) wherein the at least one additive is intentionally added and selected from the group consisting of:
(A) a salt of elements of Fe, Ni, Co, W, and Cr;
(B) a pure metal of elements of Fe, Ni, Co, W, and Cr;
(C) an alloy of elements of Fe, Ni, Co, W, and Cr; and
(D) combinations of (A)-(C); and
(b) carbothermically reacting the precursor mixture to form a titanium diboride particles, the titanium diboride particles defining a titanium diboride powder;
(i) wherein, at least partially due to the at least one additive, the titanium diboride particles realize a morphology selected from the group consisting of irregular, equiaxed, plate-like, and combinations thereof; and
(ii) wherein, at least partially due to the at least one additive, the titanium diboride powder produced by the titanium diboride particles realizes a fine particle size distribution, wherein the D50 of the titanium diboride particles is less than 3 micrometers;
wherein the preparing step (a) comprises adding from 0.001 to 0.75 wt. % of the at least one additive to the plurality of reagents based on a total weight of the titanium diboride powder.

2. The method of claim 1 , comprising:
removing an undesired byproduct of the carbothermic reaction, wherein the removing comprises exposing the precursor mixture to a process gas flow during the carbothermic reacting step.

3. The method of claim 2 , wherein exposing the precursor mixture comprises directing the process gas flow through the precursor mixture during the carbothermic reacting step.

4. The method of claim 2 , wherein the process gas is selected from the group consisting of: a noble gas, hydrogen, and combinations thereof.

5. The method of claim 1 , wherein the precursor mixture comprises from 20 wt. % to 50 wt. % of the titanium dioxide.

6. The method of claim 1 , wherein the precursor mixture comprises from 10 wt. % to 35 wt. % of the carbon source.

7. The method of claim 6 , wherein the carbon source comprises graphite.

8. The method of claim 1 , wherein the precursor mixture comprises from 30 wt. % to 70 wt. % of the boron source.

9. The method of claim 1 , wherein the preparing step (a) comprises adding 0.0625-0.5 wt. % of the least one additive to the plurality of reagents based on the total weight of the titanium diboride powder.

10. The method of claim 1 , wherein the preparing step (a) comprises adding from 0.001 to 0.45 wt. % of the at least one additive to the plurality of reagents based on the total weight of the titanium diboride powder.

11. The method of claim 1 , wherein the intentionally-added, at least one additive is selected from the group consisting of: a pure metal of elements of Fe, Ni, Co, W, and Cr, and combinations of those pure metals.

12. The method of claim 1 , wherein the intentionally-added, at least one additive is selected from the group consisting of: an alloy of elements of Fe, Ni, Co, W, and Cr, and combinations of those alloys.

13. The method of claim 1 , wherein the titanium diboride particles realize a shape factors which has ratio of x, y, and z dimensions of the particles being x: y: z=10:1:1.

14. The method of claim 1 , wherein the titanium diboride particles realize a morphology of irregular.

Assignees

• Alcoa Usa Corp

Inventors

• Mcmillen James C
• Sworts Lance M
• Mosser Benjamin D

Classifications

• C04B35/58 Primary

  based on borides, nitrides, {i.e. nitrides, oxynitrides, carbonitrides or oxycarbonitrides} or silicides {(containing free binder metal C22C29/00)} · CPC title

• C01B35/04 Primary

  Metal borides · CPC title

• C04B35/58071 Primary

  based on titanium borides · CPC title

• C04B35/52

  based on carbon, e.g. graphite · CPC title

• C04B35/634

  Polymers (C04B35/636 takes precedence) · CPC title