3D printing of metal containing structures

Patent metadata

Field	Value
Publication number	US-11318435-B2
Application number	US-201916577253-A
Country	US
Kind code	B2
Filing date	Sep 20, 2019
Priority date	Sep 21, 2018
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

In an aspect, a method for making a metal-containing material comprises steps of: forming a metal-containing hydrogel from an aqueous precursor mixture using a photopolymerization; wherein the aqueous precursor mixture comprises water, one or more aqueous photosensitive binders, and one or more aqueous metal salts; and thermally treating the metal-containing hydrogel to form the metal-containing material; wherein the metal-containing hydrogel is exposed to a thermal-treatment atmosphere during the step of thermally treating; wherein a composition of the metal-containing material is at least partially determined by a composition of the thermal-treatment atmosphere during the thermally treating step.

First claim

We claim:

1. A method for making a metal-containing material, the method comprising steps of:
forming a blank hydrogel from an aqueous blank mixture using a photopolymerization or forming a blank organogel from a nonaqueous blank mixture using a photopolymerization;
wherein the aqueous blank mixture comprises water and one or more aqueous photosensitive binders;
wherein the nonaqueous blank mixture comprises a water-miscible non-water solvent;
swelling the blank hydrogel or the blank organogel using an aqueous metal salt mixture to form a metal-containing hydrogel;
wherein the aqueous metal salt mixture comprises water and one or more aqueous metal salts; and

thermally treating the metal-containing hydrogel to form the metal-containing material.

2. The method of claim 1 , wherein the step of swelling is repeated a plurality of times, each repetition of the swelling comprises using the aqueous metal salt mixture having the one or more metal salts or using a different aqueous metal salt mixture having a different one or more metal salts.

3. The method of claim 1 , wherein the metal-containing hydrogel is exposed to a thermal-treatment atmosphere during the thermally treating step; and wherein a composition of the metal-containing material is at least partially determined by a composition of the thermal-treatment atmosphere.

4. The method of claim 3 , wherein: (i) the thermal-treatment atmosphere is a reducing atmosphere and at least a portion of the metal-containing structure is a metal or metal alloy due to chemical interaction of the metal-containing hydrogel with the thermal-treatment atmosphere; (ii) the thermal-treatment atmosphere is an oxidizing atmosphere and at least a portion of the metal-containing material is a metal oxide ceramic due to chemical interaction of the metal-containing hydrogel with the thermal-treatment atmosphere; or (iii) the thermal-treatment atmosphere is an inert atmosphere and at least a portion of the metal-containing material is a metal carbide due to the thermal-treatment atmosphere being an inert atmosphere.

5. The method claim 1 , wherein the step of thermally treating comprises a first thermally treating step and a second thermally treating step, wherein:
the first thermally treating step comprises using a first thermal-treatment atmosphere;
the second thermally treating step comprises using a second thermal-treatment atmosphere; and
a composition of the first thermal-treatment atmosphere is different from a composition of the second thermal-treatment atmosphere.

6. The method of claim 5 , wherein the first thermally treating step comprises thermally treating the metal-containing hydrogel to form an intermediate metal-containing material; wherein the second thermally treating step comprises thermally treating the intermediate metal-containing material to form the metal-containing material; wherein the first thermal-treatment atmosphere comprises an oxidizing atmosphere and a composition of the intermediate metal-containing material comprises a metal oxide; and wherein the second thermal-treatment atmosphere comprises a reducing atmosphere and a composition of the metal-containing material comprises a metal or metal alloy.

7. The method of claim 1 , wherein the aqueous metal salt mixture does not comprise metal-containing particles.

8. The method of claim 1 , wherein the aqueous metal salt mixture comprises at least two different aqueous metal salts, each characterized by different metal ions.

9. The method of claim 1 , wherein the metal-containing material has a composition comprising at least two metal ions.

10. The method of claim 1 , wherein the metal-containing material has a composition characterized as a ternary or higher order material.

11. The method of claim 1 , wherein the metal-containing material is a metal or metal alloy, a ceramic, or a carbide material.

12. The method of claim 1 , wherein the metal-containing material has structure characterized as a lattice.

13. The method of claim 1 , wherein the step of forming the hydrogel comprises patterning or printing the hydrogel.

14. The method of claim 3 , wherein the step of forming comprises an additive manufacturing process.

15. The method of claim 1 , further comprising using the metal-containing material in an electrode, as a biological scaffold, in a mechanical damping device, in a heat exchanger, as a catalyst, as a solid electrolyte, as a superconductor, as a thermal insulator, as an electrical insulator, as dielectrics, as a sensors, or any combination of these.

16. The method of claim 1 , wherein the step of thermally treating comprises pyrolyzing, calcining, sintering, high temperature annealing, or a combination of these.

17. The method of claim 1 , wherein the metal-containing hydrogel has structure characterized as architected, having a three-dimensional geometry, and macroscopically monolithic.

18. The method of claim 1 , wherein the nonaqueous blank mixture comprises a water-miscible non-water solvent and one or more photosensitive binders.

19. The method of claim 1 , wherein the blank hydrogel or the blank organogel comprises less than or equal to 0.6 wt. % of metal and metal-containing chemical species.

20. A method for making a metal-containing material, the method comprising steps of:
swelling a blank hydrogel or a blank organogel with a first aqueous metal salt mixture to form a first metal-containing hydrogel;
wherein the first aqueous metal salt mixture comprises water and one or more first aqueous metal salts; wherein the one or more first aqueous metal salts comprise one or more first metal ions;
wherein the first metal-containing hydrogel has a first portion and a second portion; wherein the first metal-containing hydrogel comprises the one or more first metal ions both in the first portion and in the second portion;

wherein the method further comprises:
leaching at least a fraction of the one or more first metal ions from the second portion thereby forming a secondary portion of the first metal-containing hydrogel;
wherein the secondary portion has a lower concentration of the one or more first metal ions than the first portion of the first metal-containing hydrogel;

swelling at least the secondary portion of the first metal-containing hydrogel using a second aqueous metal salt mixture to form a second metal-containing hydrogel;
wherein the second aqueous metal salt mixture comprises water and one or more second aqueous metal salts;
wherein the one or more second metal salts comprise one or more second metal ions; and
wherein the second metal-containing hydrogel has a spatially-varying composition comprising the first portion with the one or more first metal ions and the secondary portion with the one or more second metal ions; and

thermally treating the second metal-containing hydrogel to form the metal-containing material.

21. The method of claim 20 , wherein the metal-containing material has a spatially-varying composition comprising a primary composition having the one or more first metal ions and a secondary composition having the one or more second metal ions; and wherein the metal-containing material has a primary portion having the primary composition and a secondary portion having the secondary composition.

22. The method of claim 20 , wherein a concentration of the one or more first metal ions in the secondary portion of the second metal-containing hydrogel is less than or equal to 10% of a concentration of the one or more fir

Assignees

• California Inst Of Techn

Inventors

• Yee Daryl Wei Liang
• Greer Julia R
• Lifson Max L
• Citrin Michael A

Classifications

• G03F7/0037 Primary

  Production of three-dimensional images · CPC title

• B01J13/0056 Primary

  containing inorganic material and water · CPC title

• B22F10/62

  by chemical means · CPC title

• B22F10/12

  by photopolymerisation, e.g. stereolithography [SLA] or digital light processing [DLP] · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title