Super heat-resistant silicon carbide fibers and process for producing the same.

摘要

A super heat-resistant silicon carbide fiber has an oxygen content of less than 1.0% by weight. In a process for producing the super heat-resistant silicon carbide fiber, a precursor fiber prepared by spinning a polycarbosilane having an oxygen content of less than 0.8% by weight is irradiated with a radiation in an oxygen-free atmosphere or in vacuo to make the precursor fiber infusible. The infusibilized fiber is fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000 to 2200 DEG C without exposure to an oxidizing atmosphere; or stabilized in the same atmosphere at a temperature of from 300 to 600 DEG C without exposure to an oxidizing atmosphere and fired in an oxygen-free atmosphere or in vacuo at a temperature of from 1000 to 2200 DEG C.