Patent ID: 8187525

Claim:
A method of manufacturing an article of porous cordierite ceramic material, the method comprising: providing a green body comprised of inorganic cordierite-forming components; heating the green body of inorganic cordierite-forming components to produce the article of porous cordierite ceramic material comprising a porosity of greater than 42%, wherein heating the green body of inorganic cordierite-forming components comprises: exposing the green body to a firing environment in which a temperature of the firing environment is increased in a fast-ramp stage comprising a peak portion at a ramp-up rate of greater than 75° C. per hour from an initial temperature of 1200° C. to a peak temperature less than a melting point temperature of the cordierite ceramic material and greater than or equal to 1425° C., wherein the temperature of the firing environment in the peak portion is at all points greater than an upper soak temperature, the peak temperature being more than 5° C. greater than the upper soak temperature; immediately decreasing the temperature of the firing environment from the peak temperature to a hold stage at a ramp-down rate more negative than −0.5° C./minute, immediately after which the temperature of the firing environment in the hold stage is between a lower soak temperature of about 1300° C. and the upper soak temperature of about 1430° C.; and then holding the temperature of the firing environment between the lower soak temperature and the upper soak temperature of the hold stage for a hold time; and then decreasing the temperature of the firing environment from the hold stage to the initial temperature in a cool stage immediately following the hold stage.