| 摘要 |
A method of fabricating a cordierite ceramic honeycomb structural body which includes the following steps: formulating a batch of raw materials comprising a mixture of kaolin clay, talc, alumina and other cordierite-forming materials, each included in the batch in an effective amount such that the batch is capable of yielding a fired honeycomb body whose predominant crystal phase is cordierite; intimately blending the raw materials with an effective amount of vehicle and forming aids to impart plastic formability and green strength to the raw materials and to form a plastic mixture; forming the raw materials into a green honeycomb structural body by extrusion and thereafter drying and firing the green honeycomb structural body. The firing of the green honeycomb structural body is accomplished through a four-phase heating process as follows (1) heating the green body to a first temperature ranging between about 750-850 DEG C; (2) heating to a second temperature ranging between about 1250 to 1350 DEG C; and finally, (3) to a third temperature of at least 1390 DEG C, and (4) maintaining a temperature of at least 1390 but less than 1420 DEG C, for a period of about 12 to 20 hours. In one embodiment, an oxidizing firing atmosphere, comprising no greater than about 6 % O2, is maintained at firing temperatures above the first temperature. Alternatively, a reducing as opposed to an oxidizing, firing atmosphere, comprising no greater than about 3 % CO, is maintained at firing temperatures above the first temperature. |
