Method of firing cordierite bodies

摘要

Methods of firing a cordierite green body to form a fired cordierite body. The green body comprises cordierite-forming raw materials and organic material, the body having a core portion and a skin portion. The green body is pre-heated to a pre-heat temperature that is less than a thermal decomposition temperature of the organic material. The green body is maintained at the pre-heat temperature for a period of time sufficient to minimize a temperature differential between the core portion and the skin portion. The green body is heated to a low firing temperature in a firing atmosphere sufficient to reduce a content of the organic material and to substantially remove chemically bound water from hydrous alumina. The green body is heated to a high firing temperature in a firing atmosphere sufficient to reduce the content of the organic material prior to a substantial removal of chemically bound water from clay.

主权项

1. A method of firing a cordierite body, the method comprising:
providing a green body having a core portion and a skin portion, the green body comprising cordierite-forming raw materials and organic material, wherein the cordierite-forming raw materials comprise hydrous alumina and clay; pre-heating the green body to a pre-heat temperature that is less than a thermal decomposition temperature of the organic material; maintaining the green body at the pre-heat temperature for a period of time sufficient to obtain a temperature differential between the core portion and the skin portion of less than about 50° C.; heating the green body at a first temperature average ramp rate from the pre-heat temperature to a low firing temperature in a firing atmosphere comprising a first oxygen concentration for a period of time sufficient to reduce a content of the organic material and to substantially remove chemically bound water from the hydrous alumina; and heating the green body from the low firing temperature to a high firing temperature, wherein
at least a portion of the heating from the low firing temperature to the high firing temperature is at a second temperature average ramp rate in a firing atmosphere comprising a second oxygen concentration that is greater than the first oxygen concentration for a period of time sufficient to reduce the content of the organic material, andthe content of the organic material is substantially removed prior to a removal of chemically bound water from clay.