Cordierite aluminum magnesium titanate compositions and ceramic articles comprising same

• US 8,956,436 B2
• Filed: 11/14/2012
• Issued: 02/17/2015
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Divens-Dutcher, Adriane Marie, Tepesch, Patrick David, Vileno, Elizabeth Marie
• Primary Examiner(s): ORLANDO, AMBER ROSE
• Application Number:
  US13/676,567
• Publication Number:
  US 20130111862A1
• Time in Patent Office: 825 Days
• Field of Search: 55522-524, 422169-172, 422177-182
• US Class Current: 55/523
• CPC Class Codes: B01D 39/2068 Other inorganic materials, e.g. ceramics
• CPC Class Codes: C04B 2111/00793 as filters or diaphragms
• CPC Class Codes: C04B 2111/0081 as catalysts or catalyst carriers
• CPC Class Codes: C04B 2235/3206 Magnesium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3217 Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
• CPC Class Codes: C04B 2235/3222 Aluminates other than alumino-silicates, e.g. spinel (MgAl2O4)
• CPC Class Codes: C04B 2235/3225 Yttrium oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3227 Lanthanum oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3229 Cerium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3232 Titanium oxides or titanates, e.g. rutile or anatase
• CPC Class Codes: C04B 2235/3234 Titanates, not containing zirconia
• CPC Class Codes: C04B 2235/3236 Alkaline earth titanates
• CPC Class Codes: C04B 2235/3418 Silicon oxide, silicic acids or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
• CPC Class Codes: C04B 2235/3463 Alumino-silicates other than clay, e.g. mullite
• CPC Class Codes: C04B 2235/3481 Alkaline earth metal alumino-silicates other than clay, e.g. cordierite, beryl, micas such as margarite, plagioclase feldspars such as anorthite, zeolites such as chabazite
• CPC Class Codes: C04B 2235/349 Clays, e.g. bentonites, smectites such as montmorillonite, vermiculites or kaolines, e.g. illite, talc or sepiolite
• CPC Class Codes: C04B 2235/5436 micrometer sized, i.e. from 1 to 100 micron
• CPC Class Codes: C04B 2235/5445 submicron sized, i.e. from 0,1 to 1 micron
• CPC Class Codes: C04B 2235/6021 Extrusion moulding
• CPC Class Codes: C04B 2235/656 characterised by specific heating conditions during heat treatment
• CPC Class Codes: C04B 2235/6567 : Treatment time
• CPC Class Codes: C04B 2235/80 : Phases present in the sintered or melt-cast ceramic products other than the main phase
• CPC Class Codes: C04B 2235/9607 : Thermal properties, e.g. thermal expansion coefficient
• CPC Class Codes: C04B 2235/9615 : Linear firing shrinkage
• CPC Class Codes: C04B 35/195 : Alkaline earth aluminosilicates, e.g. cordierite or anorthite
• CPC Class Codes: C04B 35/44 : based on aluminates
• CPC Class Codes: C04B 35/468 : based on barium titanates
• CPC Class Codes: C04B 35/64 : Burning or sintering processes C04B33/32 takes precedence ; powder metallurgy B22F
• CPC Class Codes: C04B 38/0006 : Honeycomb structures from one or more corrugated sheets by winding or stacking C04B38/0083
• CPC Class Codes: C04B 38/0054 : the pores being microsized or nanosized
• CPC Class Codes: C04B 38/0074 : expressed as porosity percentage
• CPC Class Codes: C04B 38/06 : by burning-out added substances by burning natural expanding materials or by sublimating or melting out added substances
• CPC Class Codes: C04B 38/0645 : Burnable, meltable, sublimable materials
• CPC Class Codes: C04B 38/068 : Carbonaceous materials, e.g. coal, carbon, graphite, hydrocarbons
• CPC Class Codes: F01N 3/021 : by means of filters

Abstract

Disclosed are ceramic bodies comprised of composite cordierite aluminum magnesium titanate ceramic compositions and methods for the manufacture of same.

Claims

1. A ceramic article comprising a first crystalline phase comprised predominantly of a solid solution of aluminum titanate and magnesium dititanate and a second crystalline phase comprising cordierite, the article having a composition, as expressed in weight percent on an oxide basis of from 4 to 10% MgO;

from 40 to 55% Al₂O₃;

from 25 to 44% TiO₂;

from 5 to 25% SiO₂, and a sintering aid, the sintering aid comprising at least one of a lanthanide oxide and yttrium oxide.

2. The ceramic article of claim 1, wherein the lanthanide oxide comprises a cerium oxide.

3. The ceramic article of claim 1, wherein the sintering aid comprises cerium oxide and at least one of yttrium oxide and a lanthanum oxide.

4. The ceramic article of claim 1 comprising a composition expressed on an oxide basis of:

a(Al₂TiO₅)+b(MgTi₂O₅)+c(2MgO.2Al₂O₃.5SiO₂)+d(3Al₂O₃.2SiO₂)+e(MgO.Al₂O₃)+f(2MgO.TiO₂)+g(X)+i(Fe₂O₃ TiO₂)+j(TiO₂)+k(Al₂O₃), wherein a, b, c, d, e, f, g, h, i, j, and k are weight fractions of each component such that (a+b+c+d+e+f+g+i+j+k)=1.00, wherein Xis the sintering aid.

5. The ceramic article of claim 4, wherein 0.3≦

a≦

0.75, 0.075≦

b≦

0.3, 0.02≦

c≦

0.5, and 0.001≦

g≦

0.05.

6. The ceramic article of claim 5, wherein 0.3≦

a≦

0.75, 0.075≦

b≦

0.3, 0.02≦

c≦

0.5, 0.0≦

d≦

0.4, 0.0≦

e≦

0.25, 0.0≦

f≦

0.1, 0.001≦

g≦

0.05, 0.0≦

i≦

0.05, 0.0≦

j≦

0.2 and 0.0≦

k≦

0.1.

7. The ceramic article of claim 5, wherein 0.0025≦

g≦

0.02.

8. The ceramic article of claim 4, wherein the sintering aid comprises a cerium oxide.

9. The ceramic article of claim 8, wherein the sintering aid further comprises at least one of yttrium oxide and lanthanum oxide.

10. The ceramic article of claim 1, wherein the ceramic article comprises a total porosity % P greater than 40% by volume.

11. The ceramic article of claim 10, wherein the ceramic article comprises a coefficient of thermal expansion, as measured between 25-1000°

C., less than or equal to 14×

10<sup>−

7</sup>/°

C.

12. The ceramic article of claim 1, wherein the sintering aid is present, on a weight percent oxide basis, in an amount in the range of from greater than 0.1 to 5 weight % relative to the total weight of the inorganic batch composition.

13. The ceramic article of claim 1 having a composition, as expressed in weight percent on an oxide basis:

of from 5 to 10% MgO;

from 40 to 50% Al₂O₃;

from 30 to 35% TiO₂; and

from 10 to 20% SiO₂.

14. The ceramic article of claim 1, comprising a median pore size d₅₀ in the range of from 10 μ

m to 30 μ

m.

15. The ceramic article of claim 14, comprising a median pore size d₅₀ in the range of from 15 μ

m to 25 μ

m.

16. A diesel particulate filter comprising the ceramic article of claim 1, wherein said diesel particulate filter comprises a honeycomb structure having a plurality of axially extending end-plugged inlet and outlet cells.

17. A ceramic article, comprising:

at least about 50 wt % of a pseudobrookite phase comprising predominately alumina, magnesia, and titania;

a second phase comprising cordierite; and

a sintering aid, comprising at least one of a lanthanide oxide and yttrium oxide.

18. The ceramic article of claim 17, wherein the lanthanide oxide comprises a cerium oxide.

19. The ceramic article of claim 17, wherein the sintering aid comprises cerium oxide and at least one of yttrium oxide and a lanthanum oxide.

20. A method of manufacturing a ceramic article, comprising:

providing an inorganic batch composition comprising a magnesia source, a silica source, an alumina source, a titania source, and at least one sintering aid;

mixing the inorganic batch composition together with one or more processing aid selected from the group consisting of a plasticizer, lubricant, binder, pore former, and solvent, to form a plasticized ceramic precursor batch composition;

shaping the plasticized ceramic precursor batch composition into a green body; and

firing the green body under conditions effective to convert the green body into a ceramic article comprising a pseudobrookite phase comprising predominately alumina, magnesia, and titania and a second phase comprising cordierite,

wherein the sintering aid comprises at least one of a lanthanide oxide and yttrium oxide.

21. The method of claim 20, wherein the lanthanide oxide comprises a cerium oxide.

22. The method of claim 21, wherein the sintering aid comprises cerium oxide and at least one of yttrium oxide and a lanthanum oxide.

23. The method of claim 20, wherein at least one sintering aid is present, on a weight percent oxide basis, in an amount in the range of from greater than 0.1 to 5 weight % relative to the total weight of the inorganic batch composition.

24. The method of claim 20, wherein the plasticized ceramic precursor batch composition is shaped by extrusion.

25. The method of claim 20, wherein the firing conditions effective to convert the green body into a ceramic article comprise heating the green body at a maximum soak temperature in the range of from 1250°

C. to 1450°

C. and maintaining the maximum soak temperature for a hold time sufficient to convert the green body into a ceramic article.