MANUFACTURE OF CARBIDE OR NITRIDE FIBER

摘要

The invention provides a process for producing fibres composed of or coated with carbides or nitrides. The process involves forming a first reaction zone (23) containing microfine particles of an oxide (or oxide precursor) of silicon or a suitable metal (e.g. boron) uniformly mixed with carbon (or a carbon precursor); forming a second reaction zone (24) comprising a layer having a thickness of 1 cm or less of a porous mass having a density of 1 g/cc or less formed of short or continuous fibres made of or coated with carbon (or carbon precursor); heating the first reaction zone (23) in a non-oxidizing atmosphere to generate a gaseous sub-oxide of the silicon or metal; simultaneously heating the second reaction zone (24) so that the gaseous sub-oxide diffuses into it and reacts with the carbon to form carbide or nitride on the fibres; and separating the resulting fibres from any carbide or nitride whiskers that may have formed in the second reaction zone. Short or continuous fibres (e.g. in the form of a fabric or paper-like sheets) consisting of or coated with carbides or nitrides can be formed in this way.