Research in the Field of Composite Materials Based on HCBS and Refractory Materials Based on the System Al2O3–SiO2–SiC. Part 31

Resumo

Rheological properties are described both for the initial (basic) bauxite composite HCBS and the same HCBS with 15% SiC, as well as with the addition of 1 and 2% of Si. The effect of adding metallic silicon is investigated, which decreases the sintering temperature and promotes formation of closed porosity. It is established that in materials containing added Si in the firing temperature range of 1300 – 1400 °C with a reduction in open porosity from 2.7 to 1.6% oxidation of SiC or Si slows down or is inhibited. Dilatometric analysis shows that during non-isothermal heating of the samples containing 10 – 30% of SiC there is a certain degree of SiC oxidation and material mullitization is retarded.