Preparation and in-situ high-temperature mechanical properties of Cf-SiCf reinforced geopolymer composites

The hybrid Cf and SiCf reinforced geopolymer (Cf-SiCf/KGP) composites were successfully prepared by a simple method that mixing a kind of hybrid fiber preform pre-developed in geopolymer resin. The microstructure evolution and high temperature mechanical properties of the composites were studied. Results showed that all the composites showed typical amorphous structure and changed to leucite after being tested above 1000 °C. The high-temperature mechanical properties of the Cf-SiCf/KGP samples decreased with the temperature increasing. The composites tested at 800 and 1000 °C showed none catastrophic failure mode, which was attributed to the interface debonding, fiber fracturing and pulling-out.