The Degradation Behavior of SiCf/SiO2 Composites in High-Temperature Environment

• Published in: Applied composite materials 2018-04, Vol.25 (2), p.353-364
• Main Authors: Yang, Xiang, Cao, Feng, Qing, Wang, Peng, Zhi-hang, Wang, Yi
• Format: Article
• Language: English
• Subjects: Ablation; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Composite materials; Flexural strength; High temperature environments; Industrial Chemistry/Chemical Engineering; Materials Science; Oxidation; Oxidation resistance; Oxyacetylene; Polymer Sciences; Recession; Retention; Shearing; Silicon carbide; Silicon dioxide; Sol-gel processes; Thermal shock
• ISSN: 0929-189X; 1573-4897
• DOI: 10.1007/s10443-017-9620-x

SiC f/ SiO 2 composites had been fabricated efficiently by Sol-Gel method. The oxidation behavior, thermal shock property and ablation behavior of SiC f /SiO 2 composites was investigated. SiC f /SiO 2 composites showed higher oxidation resistance in oxidation atmosphere, the flexural strength retention ratio was larger than 90.00%. After 1300 °C thermal shock, the mass retention ratio was 97.00%, and the flexural strength retention ratio was 92.60%, while after 1500 °C thermal shock, the mass retention ratio was 95.37%, and the flexural strength retention ratio was 83.34%. After 15 s ablation, the mass loss rate was 0.049 g/s and recession loss rate was 0.067 mm/s. The SiO 2 matrix was melted in priority and becomes loosen and porous. With the ablation going on, the oxides were washed away by the shearing action of the oxyacetylene flame. The evaporation of SiO 2 took away large amount of heat, which is also beneficial to the protection for SiC f /SiO 2 composites.