Patent ID: 7699903

Claim:
A method for the production of a porous ceramic body comprising the following steps: selecting a first ceramic powder with a first grain size class, wherein the first ceramic powder substantially comprises α-SiC grains aside from unavoidable contaminants; selecting a second ceramic powder with a second grain size class that is substantially smaller than the first grain size class, wherein the second ceramic powder substantially comprises α-SiC grains aside from unavoidable contaminants; mixing of the first and second ceramic powders to produce a powder with a bimodal grain size distribution; shaping of a molded body from the powder mixture; heating and conditioning of the molded body at a temperature from 1750 to 1950 degrees Celsius and for a period of time such that, through recrystallization of the molded body, the grains with the second grain size are dissolved and, through attachment of the material of the second ceramic grains to the first ceramic grains, these are firmly linked to each other; and layer-wide repeating of said selecting first and second ceramic powders, said mixing of the first and second ceramic powders, said shaping of a molded body, and said heating and conditioning of the molded body with ever decreasing mean grain sizes such that a gradient with regard to the mean grain size is created transverse to the layers in the ceramic body.