abstract |
A process for preparing silicon carbide fiber by the carbothermal reduction of silica fiber. In the first step of the process, a specified silica fiber is contacted with a source of elemental carbon to produce a reactant mass; the silica fiber is comprised of at least about 99.5 weight percent of silica, has a density of at least about 2.15 grams per cubic centimeter, has a diameter of from about 1 to about 100 microns and an aspect ratio of at least about 30. From about 3.2 to about 5.0 moles of carbon are present in the carbon source for each mole of the silica. The reactant mass is heated at a temperature of from about 1,400 degrees centigrade to about 2,300 degrees centigrade for at least about 0.5 hours. |