Abstract:
Skins and/or adhesive layers are formed on a porous ceramic honeycomb by applying a layer of a cement composition to a surface of the honeycomb and firing the cement composition. The cement composition contains inorganic filler particles, a carrier fluid and a clay material rather than the colloidal alumina and/or silica materials that are conventionally used in such cements. The cement compositions resist permeation into the porous walls of the ceramic honeycomb. As a result, lower temperature gradients are seen in the honeycomb structure during rapid temperature changes, which results in an increased thermal shock resistance.