High-Performance Zirconium Disilicide Ceramics Fabricated via High-Pressure and High-Temperature Sintering

Zirconium disilicide (ZrSi2) ceramics have excellent physical and chemical properties and are employed in aerospace, energy, and chemical industries. Currently, the preparation and properties of ZrSi2 ceramics have been less studied. To comprehensively study the characteristics of ZrSi2 ceramics, in this study, dense bulk ZrSi2 ceramic samples are successfully prepared by the high-pressure-high-temperature (HPHT) sintering technique. Besides, the experimental results show that the ZrSi2 ceramic samples have a relatively high density, and the Vickers hardness and fracture toughness reach 10.9 ± 0.28 GPa and 4.84 ± 0.5 MPa·m1/2, respectively. Moreover, the electrical conductivity of ZrSi2 ceramic samples is investigated by a combination of experimental characterization and theoretical calculations. Additionally, the oxidation resistance of the ZrSi2 ceramic samples is determined by adopting a simultaneous thermal analyzer, with the oxidation onset temperature exceeding 1400 °C. Finally, the microstructure of ZrSi2 ceramic samples is investigated using electron backscatter diffraction (EBSD). The outcomes of this study reveal that HPHT sintering can effectively enhance the mechanical properties and oxidation resistance of the ZrSi2 ceramics. This study provides an effective solution for the better preparation and utilization of ZrSi2 ceramics.