Synthesis of SiC whisker by microwave heating from porous precursor

SiC whiskers with different morphologies were prepared by microwave heating of porous precursor. The growth mechanism of SiC whiskers at different sintering temperatures was studied. The results indicate that SiC whiskers can be successfully synthesized at 1000 degrees C with a holding time of 20 min. However, the optimal synthesis conditions were determined to be at 1300 degrees C for 20 min. Under this condition, the SiC whiskers exhibited rapid and uniform growth, fully filling the entire cavity. This accelerated growth is attributed to the activation effect of microwave plasma. As the temperature increases, the SiC whiskers undergo reoxidation, resulting in the formation of an amorphous SiO2 layer on their surface. This creates a coated composite material, where SiC whiskers are encapsulated by SiO2. A novel method for synthesizing silicon carbide whiskers is introduced, offering a theoretical foundation for understanding the growth mechanism of SiC whiskers prepared using microwave techniques under porous conditions.