Synthesis of Monodispersed Spherical β‐Silicon Carbide Powder by a Sol‐Gel Process

Monodispersed spherical β‐SiC powder was synthesized by heating spherical gel powder derived from the hydrolysis of a mixture of phenyltriethoxysilane and tetraethyl orthosilicate. The solution was prepared in a beaker and hydrolyzed by NH 4 OH without stirring. The monodispersed spherical gel powder of submicrometer size was obtained when the added amount of NH 4 OH was greater than 16 moles per mole of silane plus alkoxide, and it became monodispersed spherical β‐SiC powder by heat‐treating at 1500°C for 4 h in an Ar atmosphere. The SiC content of the powder was 92.6 wt%.