Improving the Porosity Features Control of Ceramic Cellular Components Through a Modified Gelcasting Process

摘要

An innovative gelcasting procedure was successfully developed to produce cellular ceramic materials, having controlled porosity features, tailored for a specific application. This process combines a conventional gelcasting based on in situ polymerization of a natural gelling agent to a sacrificial template method, in which polyethylene (PE) spheres having a controlled size distribution are used as pore former. By a suitable selection of the PE spheres fraction and volume percentage, it is possible to modify some important porosity characteristics of the final component, such as the mean pore size, the total pore volume, the pore geometry as well as the pore interconnection number and size. The effectiveness and versatility of this procedure was demonstrated by exploiting it in the preparation of porous components made of several ceramic powders (alumina, zirconia, hydroxyapatite) different in terms of composition and size.