S-Space College of Engineering/Engineering Practice School (공과대학/대학원) Dept. of Chemical and Biological Engineering (화학생물공학부) Journal Papers (저널논문_화학생물공학부)
Formation of Silica-Coated Carbon Powder and Conversion to Spherical -Silicon Carbide by Carbothermal Reduction
- Jung, Yoon Seok; Kwon, Ou Jung; Oh, Seung M.
- Issue Date
- Blackwell Publishing
- J. Am. Ceram. Soc., 85 2134-36 (2002)
- Spherical -SiC powders that are a few micrometers in size
have been prepared by heating a mixture of phenolic resin
powder and fine-grained fumed silica at 1600°C in argon. The
overall process is composed of two consecutive steps: (i) the
formation of silica-coated spherical carbon powder and (ii)
carbothermal reduction. The irregularly shaped resin powder
transforms to a spherical-shaped morphology in the first step,
and the resulting silica-coated spherical carbon powder is
converted to -SiC in the second step. The key factor in the
first step is the utilization of fumed silica that has hydrophobic
surface functional groups. Hydrophobic interactions at the
point of intimate contact between the resin powder and the
silica likely reduce the surface energy of the resin powder,
thereby discouraging interparticle coalescence. The resulting
-SiC powder exhibits a radially developed columnar microstructure.
Hollow -SiC spheres also can be prepared by
controlling the reaction conditions in the carbothermal reduction step.
- 0002-7820 (print)
- Files in This Item: There are no files associated with this item.