Carbon-silica alloy material as silicon carbide precursor prepared from phenol resin and ethyl silicate

Three kinds of inorganic-organic hybrid gel sheets were prepared from the l iquid mixtures of ethyl silicate and water-soluble phenol resin. The prepar ed transparent gel sheets were fired at various temperatures. The density o f the fired sheets jumped up at 773-1023 K with disappearance of organic gr oups. The sheets kept the prepared shape after the 1273 K firing, and their density increased with the silica content. After the firing at 1873 K, the sheets with high carbon content (C/SiO2: 5.60, 3.52) were converted into t he sheets composed of silicon carbide aggregate with excess carbon, while t he sheet with low carbon content (C/SiO2: 1.43) was converted into the frag ile powders.