Microstructure and Mechanical Properties of C/C-ZrC-SiC Composites Fabricated by Reactive Melt Infiltration with Zr, Si Mixed Powders

To meet the increasing demand for advanced materials capable of operation over 2000 °C for future thermal protection systems application, C/C-ZrC-SiC composites were fabricated by reactive melt infiltration (RMI) with Zr, Si mixed powders as raw materials. The structural evolution and formation mechanism of the C/C-ZrC-SiC composites were discussed, and the mechanical property of the as-prepared material was investigated by compression test. The results showed that after the RMI process, a special structure with ZrC-SiC multi-coating as outer layer and ZrC-SiC-PyC ceramics as inner matrix was formed. ZrC and SiC rich areas were formed in the composites and on the coating surface due to the formation of Zr-Si intermetallic compounds in the RMI process. Mechanical tests showed that the average compression strength of the C/C-ZrC-SiC composites was 133.86 MPa, and the carbon fibers in the composites were not seriously damaged after the RMI process.