Effect of Sintering Process on Microstructure and Properties of (Zr0.2Ta0.2Ti0.2Cr0.2Hf0.2)Si2 High-Entropy Silicide Ceramics

In this study, five kinds of (Zr0.2Ta0.2Ti0.2Cr0.2Hf0.2)Si2 high-entropy ceramics were prepared by a two-step method under different vacuum pressureless pre-sintering processes, and the microstructures and mechanical properties of the ceramics under different parameters of the pre-sintering process were systematically discussed. The results show that the physical structure of the ceramic samples remains basically unchanged by changing the pre-sintering conditions; the longer the holding time of the initial pre-sintering, the higher the densification of the samples and all of them are above 95%. The hardness of the ceramics was around 10 GPa, with the best hardness of 10.11 GPa at 1300 °C for 3 h. This conclusion provides data support for the optimization of the high-entropy ceramics preparation process.