Study of the structure of yttrium-based nanoporous ceramic materials

Abstract

Porous ceramic materials with high filtration performance are widely used in conditions of high chemical, thermal and radiation loads. The results of studying the structure and morphology of the pore space of ceramic membranes are presented. Ultradispersed refractory powder Y2O3 was used as a main component-filler. The synthesis was carried out using compaction, technological combustion and self-propagating high-temperature synthesis. The use of ultradisperse sintering additives with highly developed surface (MgO — 5 μm, SiC — 3, SiO2 — 5 μm) allowed us to ensure the energy efficiency of synthesis of high- porous ceramic materials at low temperatures. Analysis of the structure and pore space using mercury porometry and alternative methods showed that the average pore size in the synthesized 3D matrix composite material based on yttrium orthosilicate matrix with yttrium oxide filler is 1.1 μm, the equivalent hydraulic pore diameter being about 100 nm. The difference is attributed to the variability of cross sections and high tortuosity of pore channels. Since the density of the material is 2.3 g/cm3 and the compressive strength is about 2 MPa, it can be easily machined with carbide tools being a promising material for manufacturing products with complex shapes. The obtained results can be used in developing energy-efficient technologies of one-stage production of yttrium oxide-based filters with high porosity to be used under conditions of exposure to radiation, aggressive media and high temperatures.