Effect of Spark Plasma Sintering on Densification and Mechanical Properties of Silicon Carbide

TLDR

Silicon carbide ceramics containing 5 wt % Al₂O₃ and 2 wt % Y₂O₃ were fabricated by spark plasma sintering at 30 MPa for 5 min, and their room‑temperature mechanical properties were subsequently evaluated. Spark plasma sintering produced dense silicon carbide at 1800 °C—about 200 °C lower than hot‑pressing—and yielded higher strength and fracture toughness, indicating that the actual internal temperature during SPS exceeds the measured value.

Abstract

Silicon carbide ceramics which 5 mass% Al2O3 and 2 mass% Y2O3 were added to were prepared by the spark plasma sintering (SPS) method under the conditions of 30 MPa and 5 min. Mechanical properties at room temperature were eximined. The SPS brought dense silicon carbide ceramics at a sintering temperature of 1800°C, which was about 200°C lower than that of the hot-pressing process. The silicon carbide obtained by SPS had higher strength and fracture toughness than those obtained by hot-pressing. The results suggest that the inside temperature of the sintered bodies during spark plasma sintering was higher than the measured temperature.