Low-temperature and pressureless fabrication of high-purity SiC-ZrC ceramics free of residual melts via reactive melt infiltration

Conventional methods like hot pressing (HP) for fabricating SiC-ZrC ceramics typically require high temperatures and external pressure, which can significantly degrade the performance of SiC fibers and restrict the nuclear application of SiC-ZrC composites. In contrast, this work successfully fabricated dense, high-purity SiC-ZrC ceramics with no obvious residual Si using a relatively low-temperature and pressureless RMI method. An obvious correlation between byproduct ZrSi 2 and processing temperature was observed. Notably, significant phase homogeneity differences were observed in the ceramics obtained from pure Si versus Si-Zr alloy infiltration. The low-temperature and pressureless preparation process of the RMI method in this study has promoted the application of SiC-ZrC ceramics as a modified matrix in SiC f /SiC composites for accident-tolerant fuel (ATF) cladding.