Reactive Hot-Pressed Hybrid Ceramic Composites Comprising SiC(SCS-6)/Ti Composite and ZrB2-ZrC Ceramic

In this study, hybrid composites comprising SiC(SCS-6)/Ti and ZrB2-ZrC ceramics were prepared by sandwiching Ti/SiC (SCS-6)/Ti sheets and Zr + B4C powder layers, followed by reactive hot pressing at 1300 degrees C. The microstructure of the obtained hybrid composites was characterized by field-emission scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results show that after reactive hot pressing, a highly dense matrix was achieved in the hybrid composites. A Ti-rich zone was observed only in the hybrid composite prepared using a 10-mu m-thick Ti foil. Interface reaction occurred during sintering and interface reaction layers were formed between the fibers and the matrix, and the phases were identified. In addition, the mechanical behavior of the hybrid composites was evaluated using by testing under four-point bend testing. The results indicate that the hybrid composites exhibited greater flexural strengths and noncatastrophic fracture behavior. The flexural strength ranged from 440 to 620 MPa, depending on the thickness of the Ti foils and the fiber volume amount.