To understand these results,XRD and XPS analyses were done to identify the crystal structures and bonding structures
in the media,and the analysis results are shown in Figs. 6, 7. The intensity of SiC phase increased with increasing sintering
temperatures below 1450 C,resulting from the rigid crystallization of SiC species by increasing temperature.However,the intensity of SiC species decreased with increasing sintering temperatures above1450 C. The formation of abnormal bonding structure by over-firing might be a reason.
We also found that the intensity of SiO2 species increased continuously with increasing sintering temperature.In a previous study,the oxidation degree of SiC increased with
increasing sintering temperature,and it had an inversely proportional relationship to mechanical strength