Process for producing a non-dense sintered ceramic molded body having at least two layers

Abstract

A process for producing a non-dense sintered ceramic molded body having at least two layers, wherein a first powdery ceramic material forming a layer is contacted with at least a second powdery material forming at least a second layer; said first powdery material has a presintering temperature Tthat is higher than the presintering temperature Tof said at least second powdery ceramic material; the course of a curve of shrinkage Sof said at least first powdery ceramic material differs from the course of a curve of shrinkage Sof said at least second powdery material, wherein curve of shrinkage Sis shifted towards higher temperatures as compared to curve of shrinkage S; and the layers are subjected to a common temperature treatment at a presintering temperature Tthat is lower than the presintering temperature Tand at least equal to Tto cause sintering that remains in a stage of sintering that has not proceeded to the theoretical density; wherein the curve of shrinkage Sis modified by admixing at least one component having a curve of shrinkage Swhich material is compatible with said powdery ceramic material into said first powdery ceramic material, i. e. has a grain size smaller than the first powdery ceramic material, to equalize the curves of shrinkage Sand Sin the region of the presintering temperature T.