An engineering ceramic-used high-temperature-resistant inorganic phosphate-based adhesive self-reinforced by in-situ growth of mullite whiskers

Mullite whiskers were successfully in-situ synthesized in phosphate-based adhesive by taking Si and Al(OH)3 as reaction sources and AlF3 as the catalytic initiator. After calcination at 1300 °C, both strength and toughness of whisker-growth adhesive got greatly improved, which were increased by 75% and 156%, respectively. The bonding strength was enhanced to 23.8 MPa, which was close to some hot preceramic polymer-based adhesives. An approximate yield stage appeared on its corresponding loading-curve, showing unprecedented toughness and high damage capacity. In addition, the residual rate of bonding strength still maintained 63% after 20 thermal cycles (room temperature-1300 °C).