Mechanical and interfacial behavior of single mullite fiber and mullite fiber-based porous ceramics

The mechanical behaviors of single mullite fiber and binder/mullite fiber interface were experimentally investigated. The growth of the mullite grains of the fiber with the increasing calcination temperature greatly affected the tensile and compression strengths of the mullite fibers. As the calcination temperature went up from 1000 °C to 1500 °C, the average tensile strength decreased from 0.954 GPa to 0.191 GPa, and the Weibull modulus decreased from 5.1 to 1.8. The compressive strength was 50–60% of the average tensile strength under the same calcination temperature. The bonding strength of the binder/fiber interface increased with the increase of the calcination temperature. The mechanical properties and fracture mechanism of the mullite fiber-based porous ceramics with different binder contents were comprehensively analyzed based on the mechanical behavior of the single mullite fiber and the binder/fiber interface.