Formation and Mechanical Properties of β-SiC Whiskers by Thermal Decomposition of Sulfur-Containing Silicone Oils

β-SiC whiskers were grown by thermal decomposition of two kinds of sulfur-containing silicone oils at 1200°-1400°C. Yield of the whiskers was maximum at 1300°C, and was higher for the oil containing a larger amount of sulfur. The products were white and wooly whiskers having high aspect ratios, 0.1-0.4μm wide and 0.5-9cm long, the aspect ratios and dimensions being dependent on the reactant oils and reaction temperature. The whiskers were triangular rod-form. The growth axis was identified to be ‹111› of β-SiC and side faces were {211} planes. Tensile strength of the whiskers with apparent diameter 1.7-2.9μm was 1.7-14.9GPa, approximately the same as those obtained by other reactions. Many stacking faults were observed obliquely against the whisker axis by electron microscopy, but the existence of stacking faults exerted no influence on the mechanical properties. In addition, there were no perfect dislocations which might result in the lowering of mechanical properties.