Silicon Carbide/Polysilazane Composite: Effect of Temperature on the Densification, Phase, and Microstructure Evolution

Abstract

This paper reports a route to suppress the grain growth in silicon carbide (SiC) during its sintering by combining it with polysilazane (PSZ). SiC was mixed with PSZ in a 1:1 weight ratio and sintered at 1600, 1700, and 1800 °C in a hot-pressing furnace. A satisfactory density was obtained at sintering temperatures > 1600 °C. The grain sizes of the SiC/PSZ composites sintered at 1700 and 1800 °C were 112 and 125 nm, respectively. The grain shape of the SiC/PSZ composite sintered at 1700 °C was circular and mainly similar to the initial shape of the SiC powder. Grain shape accommodation was observed at a sintering temperature of 1800 °C. It is suggested that different sample shapes were affected by different liquid phase formations. Silicon oxynitride (Si2N2O) was formed and played an important role in densification and microstructure generation.

The Effect of Thermal Treatment on the Characteristics of Porous Ceramic-Based Natural Clay and Chitosan Biopolymer Precursors

“…This anomalous behavior can be explained by assuming that a high defect concentration is produced during densification at 1000 °C; it can be attributed to the low crystallinity of the specimen at a sintering temperature of 1000 °C (Fig. 5) and associated rapid particle deformation [51]. In order to confirm the structural parameters of the specimens, the Williamson-Hall was also used to determine the strain using Eq.…”