Patent ID: 7976768

Claim:
A method of manufacturing an aluminum titanate containing ceramic article, comprising the steps of: mixing inorganic batch materials with a pore former combination to form a batch composition, said pore former combination including a first pore former and a second pore former of differing composition; adding an organic binder and a solvent to the batch composition and further mixing to form a plasticized mixture; forming a green body from the plasticized mixture; and firing the green body to produce a prominent phase of aluminum titanate, wherein the step of firing further comprises the steps of: increasing a furnace temperature in a first stage at a first average ramp rate of greater than 14° C./hour and less than 50° C./hour to burn out the first pore former, holding the furnace temperature substantially constant in a second stage within a first hold zone having a lower limit above 500° C. and a upper limit below 900° C. for between 10 and 120 hours to burn out the second pore former, increasing the furnace temperature in a third stage at a second average ramp rate of greater than 30° C./hour and less than 80° C./hour, holding the furnace temperature in a fourth stage and within a second hold zone having a lower limit above 1350° C. and an upper limit below 1550° C. for at least 4 hours; wherein the oxygen level in the furnace is controlled during firing by the following steps: holding the oxygen level at a level of less than 10% during the first stage, increasing the oxygen to a level that is less than 15% during the second stage, and increasing the oxygen to a level that is less than 30% during the third stage.