Method of hydrothermal liquid phase sintering of ceramic materials and products derived therefrom

• US 8,313,802 B2
• Filed: 11/14/2008
• Issued: 11/20/2012
• Est. Priority Date: 11/15/2007
• Status: Active Grant

• Current Assignee: Rutgers University
• Original Assignee: Rutgers University
• Inventors: Riman, Richard E., Atakan, Vahit
• Primary Examiner(s): Fletcher, III, William Phillip
• Application Number:
  US12/271,513
• Publication Number:
  US 20090142578A1
• Time in Patent Office: 1,467 Days
• Field of Search: 427230-239, 427/333, 427/337, 427/343, 427/344
• US Class Current: 427/230
• CPC Class Codes: C04B 2235/3208 Calcium oxide or oxide-forming salts thereof, e.g. lime
• CPC Class Codes: C04B 2235/3213 Strontium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3215 Barium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3256 Molybdenum oxides, molybdates or oxide forming salts thereof, e.g. cadmium molybdate
• CPC Class Codes: C04B 2235/3262 Manganese oxides, manganates, rhenium oxides or oxide-forming salts thereof, e.g. MnO
• CPC Class Codes: C04B 2235/3275 Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
• CPC Class Codes: C04B 2235/3279 Nickel oxides, nickalates, or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3296 Lead oxides, plumbates or oxide forming salts thereof, e.g. silver plumbate
• CPC Class Codes: C04B 2235/608 Green bodies or pre-forms with well-defined density
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 35/2658 Other ferrites containing manganese or zinc, e.g. Mn-Zn ferrites
• CPC Class Codes: C04B 35/2666 Other ferrites containing nickel, copper or cobalt
• CPC Class Codes: C04B 35/2683 Other ferrites containing alkaline earth metals or lead
• CPC Class Codes: C04B 35/42 based on chromites C04B35/047 and C04B35/105 take precedence
• CPC Class Codes: C04B 35/447 based on phosphates , e.g. hydroxyapatite
• CPC Class Codes: C04B 35/457 based on tin oxides or stannates
• CPC Class Codes: C04B 35/4682 based on BaTiO3 perovskite phase
• CPC Class Codes: C04B 35/47 based on strontium titanates
• CPC Class Codes: C04B 35/49 containing also titanium oxides or titanates
• CPC Class Codes: C04B 35/491 based on lead zirconates and lead titanates , e.g. PZT
• CPC Class Codes: C04B 35/495 : based on vanadium, niobium, tantalum, molybdenum or tungsten oxides or solid solutions thereof with other oxides, e.g. vanadates, niobates, tantalates, molybdates or tungstates
• CPC Class Codes: C04B 35/64 : Burning or sintering processes C04B33/32 takes precedence ; powder metallurgy B22F
• CPC Class Codes: Y10T 428/249921 : Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/249956 : Void-containing component is inorganic
• CPC Class Codes: Y10T 428/249957 : Inorganic impregnant
• CPC Class Codes: Y10T 428/24999 : Inorganic

Abstract

Provided here is a method of producing a monolithic body from a porous matrix, comprising: (i) providing a porous matrix having interstitial spaces and comprising at least a first reactant; (ii) contacting the porous matrix with an infiltrating medium that carries at least a second reactant; (iii) allowing the infiltrating medium to infiltrate at least a portion of the interstitial spaces of the porous matrix under conditions that promote a reaction between the at least first reactant and the at least second reactant to provide at least a first product; and (iv) allowing the at least first product to form and fill at least a portion of the interstitial spaces of the porous matrix, thereby producing a monolithic body, wherein the monolithic body does not comprise barium titanate.

Claims

1. A method of producing a monolithic body from a porous matrix, comprising:

(i) providing a porous matrix having interstitial spaces and comprising at least a first reactant;

(ii) contacting the porous matrix with an infiltrating medium that carries at least a second reactant;

(iii) allowing the infiltrating medium to infiltrate at least a portion of the interstitial spaces of the porous matrix under conditions that promote a reaction between the at least first reactant and the at least second reactant to provide at least a first product, wherein a reaction temperature is less than about 250°

C.; and

(iv) allowing the at least first product to form and fill at least a portion of the interstitial spaces of the porous matrix, thereby producing a monolithic body, wherein the first product does not comprise barium titanate,

wherein the step (iv) further comprises aging the monolithic body.

2. The method of claim 1, wherein the first reactant comprises a metal oxide, metal hydroxide, metal sulfate, metal fluoride, metal titanate, or a combination thereof.

3. The method of claim 1, wherein the porous matrix further comprises an inert fill material that decomposes when heated.

4. The method of claim 1, wherein the second reactant comprises an oxalate, a carbonate, a sulfate, a phosphate, a citrate, a metal ion, a mixture of metal salts, or a combination thereof.

5. The method of claim 1, wherein the infiltrating medium is a non-aqueous solution.

6. The method of claim 1, wherein the first product is formed by ion addition, ion substitution, disproportionation, precipitation, or a combination thereof.

7. The method of claim 1, further comprising repeating the steps (ii) to (iv) at least once.

8. A method of producing a non-barium titanate sintered ceramic, comprising:

(i) providing a porous matrix having interstitial spaces and comprising at least a first reactant;

(ii) contacting the porous matrix with an infiltrating medium that carries at least a second reactant;

(iii) allowing the infiltrating medium to infiltrate at least a substantial portion of the interstitial spaces of the porous matrix under conditions that include a reaction temperature of less than about 250°

C. and a reaction pressure of less than about 70000 psi and which promote a reaction between the at least first reactant and the at least second reactant to provide at least a first product; and

(iv) allowing the at least first product to form and fill at least a substantial portion of the interstitial spaces of the porous matrix, thereby producing a non-barium titanate sintered ceramic.

9. The method of claim 8, wherein the porous matrix comprises a metal oxide.

10. The method of claim 8, wherein the second reactant comprises a salt of at least one type of metal.

11. The method of claim 8, wherein the reactant in step (iv) is formed by ion addition, ion substitution, disproportionation, precipitation or a combination thereof.

12. A method of producing a composition, comprising:

(i) providing a porous matrix having a molar volume;

(ii) immersing at least a portion of the porous matrix in an infiltrating medium having a reactant; and

(iii) forming a product by reacting at least some of the reactant with at least a portion of the matrix to provide a composition having an interconnecting microstructure, wherein a reaction temperature is less than about 250°

C., wherein the product has a molar volume,

wherein the molar volume of the matrix before step (iii) is smaller than that of the product after step (iii).

13. The method of claim 12, wherein the solid matrix does not dissolve in the infiltrating medium readily.

14. The method of claim 12, wherein the matrix comprises an inert fill material.

15. The method of claims 12, wherein the product has a net shape the same as the porous matrix.

16. A method of producing a monolithic body from a porous matrix, comprising:

(i) providing a porous matrix having interstitial spaces and comprising at least a first reactant;

(ii) contacting the porous matrix with an infiltrating medium that carries at least a second reactant;

(iii) allowing the infiltrating medium to infiltrate at least a portion of the interstitial spaces of the porous matrix under conditions that promote a reaction between the at least first reactant and the at least second reactant to provide at least a first product, wherein a reaction temperature is less than about 250°

C.; and

(iv) allowing the at least first product to form and fill at least a portion of the interstitial spaces of the porous matrix, thereby producing a monolithic body, wherein the first product does not comprise barium titanate,

wherein the monolithic body is produced in step (iv) by Ostwald ripening.

17. The method of claim 16, wherein the monolithic body has a residual porosity of about 15 percent or less by volume.

18. A method of producing a composition, comprising:

(iii) providing a porous matrix having a molar volume;

(iv) immersing at least a portion of the porous matrix in an infiltrating medium having a reactant; and

(iii) forming a product by reacting at least some of the reactant with at least a portion of the matrix to provide a composition having an interconnecting microstructure, wherein a reaction temperature is less than about 250°

C., wherein the product has a molar volume;

wherein the molar volume of the matrix before step (iii) is larger than that of the product after step (iii).

19. The method of claim 18, wherein the solid matrix does not dissolve in the infiltrating medium readily.

20. The method of claim 18, wherein the matrix comprises an inert fill material.

21. The method of claims 18, wherein the product has a net shape the same as the porous matrix.