Study Of The Properties Of Sic Composites Combined By Superfine Sio₂

According to analyzing the application of kiln furniture and the performance which they need, introduced the outstanding performance of the metal plastiscal phases compound materials and the classification of the SiC kiln, emphasized the properties of the SiO₂-SiC kilns. We produced three kind of specimens in order to study the influence on the properties of the kiln furniture, by different content of SiO₂ superfine powder, Si powder and Ti powder joined into the materials. The physical performance (line change rate, bulk density and apparent porosity), mechanical properties on normal temperature (flexural strength and compression strength on normal temperature), and mechanical properties on high temperature (flexural strength on high temperature and resistance to thermal shock properties) were tested. Compared the change of properties by change the content of SiO₂ superfine powder, Si powder and Ti powder, optimizing each powder content in order to get the best component step by step. The research show that when the content of the SiO₂ superfine power is 3.5% and Si powder is 3.5%, the materials have lower apparent porosity and higher bulk density, and the flexural strength and compression strength on normal temperature were great, and has the steady properties in high temperature. Based on that, different additive of Ti powder has been added, and the XRD technology which used to analyze the phases of samples. The microstructure was observed by scanning electron microscopy (SEM) system and EDAX, and discussed the reactive mechanism by DSC. The material has the best properties when the content of SiO₂ superfine power, Si powder and Ti powder is 3.5%, 3.5%, 2.0% separately.