Fast firing method for high porosity ceramics

Patent metadata

Field	Value
Publication number	US-9446560-B2
Application number	US-201313951802-A
Country	US
Kind code	B2
Filing date	Jul 26, 2013
Priority date	Jul 26, 2013
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

A method for firing a green honeycomb ceramic body including heating the green honeycomb ceramic body from room temperature to a first temperature of about 300° C. The green honeycomb ceramic body is then heated from the first temperature to a second temperature of greater than or equal to about 800° C. at a heating rate of greater than or equal to about 90° C./hr. The green honeycomb ceramic body may have a diameter of from greater than or equal to about 4.0 inches to less than or equal to about 9.0 inches, and it may include a carbon-based pore former in a concentration of from greater than or equal to about 10% to less than or equal to about 45% by weight.

First claim

What is claimed is:

1. A method for firing a green honeycomb ceramic body, the method comprising:
heating the green honeycomb ceramic body from room temperature to a first temperature of about 300° C.; and
heating the green honeycomb ceramic body from the first temperature to a second temperature of greater than or equal to about 800° C. at a heating rate of greater than or equal to about 90° C./hr,
wherein the green honeycomb ceramic body has a diameter of from greater than or equal to about 4.0 inches to less than or equal to about 9.0 inches,
wherein the green honeycomb ceramic body comprises a carbon-based pore former in a concentration of from greater than or equal to about 10% to less than or equal to about 45% by weight, and
wherein heating the green honeycomb ceramic body from the first temperature to the second temperature comprises a different heating rate than a heating rate during heating the green honeycomb ceramic body from room temperature to the first temperature.

2. The method of claim 1 , wherein heating the green honeycomb ceramic body from room temperature to the first temperature comprises:
heating the green honeycomb ceramic body from room temperature to a temperature of from about 215° C. to about 250° C.; and
heating the green honeycomb ceramic body from the temperature of from about 215° C. to about 250° C. to the first temperature at a heating rate of greater than or equal to about 90° C./hr.

3. The method of claim 2 , wherein heating the green honeycomb ceramic body from room temperature to the temperature of from about 215° C. to about 250° C. comprises:
heating the green honeycomb ceramic body from room temperature to a temperature of from about 150° C. to about 205° C. at a heating rate of from greater than or equal to about 60° C./hr to less than or equal to about 80° C./hr; and
heating the green honeycomb ceramic body from the temperature of from about 150° C. to about 205° C. to the temperature of from about 215° C. to about 250° C. at a heating rate of less than or equal to about 20° C./hr.

4. The method of claim 1 , wherein heating the green honeycomb ceramic body from room temperature to the first temperature comprises heating at a heating rate of greater than or equal to about 90° C./hr.

5. The method of claim 1 , wherein heating the green honeycomb ceramic body from room temperature to the first temperature comprises heating at a heating rate of from greater than or equal to about 90° C./hr to less than or equal to about 150° C./hr.

6. The method of claim 1 , wherein heating the green honeycomb ceramic body from the first temperature to the second temperature comprises heating at a heating rate of less than or equal to about 150° C./hr.

7. The method of claim 1 , wherein the second temperature is about 900° C. and the green honeycomb ceramic body is heated from the first temperature to the second temperature at a heating rate of from greater than or equal to about 90° C./hr to less than or equal to about 125° C./hr.

8. The method of claim 1 , wherein
the second temperature is less than or equal to about 1000° C., and
the method further comprises heating the green honeycomb ceramic body from the second temperature to a third temperature of greater than or equal to about 1050° C. at a heating rate sufficient to remove carbonaceous material remaining in the green honeycomb ceramic body after it has been heated to the second temperature.

9. The method of claim 8 , further comprising:
heating the green honeycomb ceramic body from the third temperature to a top soak temperature;
holding the green honeycomb ceramic body at the top soak temperature; and
cooling the green honeycomb ceramic body from the top soak temperature to room temperature to form a cordierite ceramic body.

10. The method of claim 8 , wherein the green honeycomb ceramic body is heated from the second temperature to the third temperature at a heating rate of less than or equal to about 20° C./hr.

11. The method of claim 8 , wherein the green honeycomb ceramic body is heated from the second temperature to the third temperature at a heating rate of greater than or equal to about 60° C./hr.

12. The method of claim 1 , wherein an oxygen content of an atmosphere present during heating of the green honeycomb ceramic body from room temperature to the first temperature is from about 5% to about 8%.

13. The method of claim 1 , wherein an oxygen content of an atmosphere present during heating of the green honeycomb ceramic body from the first temperature to the second temperature is from about 7% to about 13%.

Assignees

• Corning Inc

Inventors

• Bronfenbrenner David Jack
• Iyer Sriram Rangarajan

Classifications

• C04B38/0006

  Honeycomb structures (from one or more corrugated sheets by winding or stacking C04B38/0083) · CPC title

• C04B2235/77

  Density · CPC title

• C04B2111/00793

  as filters or diaphragms · CPC title

• C04B2235/656

  characterised by specific heating conditions during heat treatment · CPC title

• B28B11/243

  Setting, e.g. drying, dehydrating or firing ceramic articles (B28B11/242 takes precedence) · CPC title