Silicon carbide fiber having boron nitride layer in fiber surface and process for the production thereof

摘要

A silicon carbide fiber having a boron nitride layer in a fiber surface and having the following properties of a to c, a. the existent ratio of boron slopingly increases towards the surface of the fiber, b. the existent ratio of boron in the region of from the fiber surface to a depth of 500 nm is 0.5 to 1.5% by weight, c. the existent ratio of boron in a fiber central portion which is a region of a depth of at least 3 mum below the fiber surface is 0 to 0.2% by weight, and a process for the production thereof.