Effect of Activator on Properties of SiC Porous Ceramics

Abstract

In this study, porous silicon carbide ceramics were prepared by using silicon carbide as the main material and sodium carboxymethyl cellulose (CMC) as the pore-forming agent. SiO2-Y2O3-Al2O3 and SiO2-kaolin were used as the builders respectively. This study is about the effect of SiO2-Y2O3-Al2O3 and SiO2-kaolin content on the structure and mechanical properties of porous silicon carbide.

SiO2-Y2O3-Al2O3 and SiO2-kaolin affect the porosity, hardness and flexural strength of silicon carbide porous ceramics. In this experiment, the porosity of porous ceramics was measured by Archimedes method. The hardness was measured by Rockwell hardness tester. The flexural strength was measured by universal testing machine. The results show that the properties of silicon carbide porous ceramics prepared by SiO2-Y2O3-Al2O3 are better than that of SiO2-kaolinite when the SiO2 -Y2O3-Al2O3 content is 20%. With SiO2-Y2O3-Al2O3 as the combustion agent, porous ceramic with better performance can be prepared at 1500 ℃. When the SiO2-Y2O3-Al2O3 content is 20%, the prepared silicon carbide porous ceramics has a large porosity and excellent mechanical properties, the opening porosity of 23.73%, hardness and flexural strength of 62 and 15.47MPa, from the fracture can be seen more porous and evenly distributed.