Method of making porous ceramic suitable as diesel particulate filters.

摘要

A method of making porous ceramic articles is disclosed that allows the formed green body to be dried in a dielectric oven without arcing or shorting occurring while maintaining favorable physical properties. The method includes adding water insoluble cellulose and graphite to the ceramic-forming precursors as a burnout material. The method of the present invention is particularly useful in forming porous cordierite articles that are extruded to form a honeycomb structure conventionally used as a particulate filter for the exhaust fluids of diesel engines. Such articles have a matrix of thin walls forming a multiplicity of open-ended cells extending from one end to another end of the honeycomb. The thin walls have a substantially smaller coefficient of thermal expansion in the direction parallel to the axes of the open-ended cells than in the direction transverse to the thin walls.