Correlation of microstructure and mechanical properties of various fabric reinforced geo-polymer composites after exposure to elevated temperature

This article presents the correlation between microstructure and mechanical properties such as flexural strength, flexural modulus of fabric reinforced geo-polymer composite after their exposure to elevated temperature (up to 1000 °C). Geo-polymer matrices with Si:Al ratio of 15.6 were synthesized and the samples of geo-polymer composite were fabricated with three different types of fabric reinforcements such as carbon, E-glass and basalt fibers. The residual strength of carbon based geo-polymer composite increased with increase of the processing temperature after 600 °C. The basalt reinforced geo-polymer composite strength decreased at higher processing temperature, which may be due to the strong interaction between matrix and fiber and transformation of the composite into a ceramic-like structure. The non-adhesion of E-glass fiber to geo-polymer matrix and pyrolysis of the fiber at high temperature has been observed in the composite. Carbon reinforced geo-polymer composite can be possible candidate for the high temperature applications in thermal barrier coatings and panels.