Spark Plasma Sintering of ZrB2–SiC–ZrC Nanocomposit Synthesized by MASPS

ZrB2–SiC–ZrC nanocomposite were fabricated by spark plasma sintering (SPS) using ZrB2–SiC–ZrC synthesized powder by MA-SPS route. In the present research, sintering mechanism was investigated by displacement-temperature-time (DTT), displacement rate vs. temperature and displacement rate vs. time diagrams which were obtained during spark plasma sintering cycles. Sintering process of the composite was completed after 17 min at temperature of 1750°C. By using X-ray powder diffraction (XRD) pattern and Rietveld method, the mean crystallites sizes of about 77, 62 and 56 nm were calculated for ZrB2, SiC and ZrC phases, respectively. The physical and mechanical properties of sintered composite such as: density, Flexural strength, Vickers hardness and fracture toughness were % 99/3, 563 MPa, 18 GPa and 4.9 MPa.m1/2, respectively. Finally scanning electron microscopy (SEM) images show three different phases well distributed all over the sample. It is clear that ZrB2, SiC and ZrC phases are well connected and have good continuity.