FACILITATING PITCH STABILIZATION IN DENSIFIED CARBON FIBER PREFORMS

摘要

A method of forming a densified preform or composite part is disclosed that includes partially densifying a porous preform, forming channels in the partially densified preform that open to an exterior surface of the partially densified preform, infiltrating a densifying agent, such as pitch, into at least some of the channels of the partially densified preform, at least partially stabilizing the densifying agent, including heating at a first temperature, such that cracks form within the densifying agent, and exposing the preform to an oxidizing agent, and heating the at least partially stabilized preform at a second temperature to carbonize at least the stabilized densifying agent. A partially densified preform including a densifying agent disposed at least in such channels also is disclosed.

主权项

1. A method comprising:
partially densifying a porous preform to form a partially densified preform; forming a plurality of channels in the partially densified preform, wherein each channel of the plurality of channels opens to at least one exterior surface of the partially densified preform; infiltrating a densifying agent into at least some channels of the plurality of channels formed in the partially densified preform to form an infiltrated preform; at least partially stabilizing the densifying agent to form an at least partially stabilized preform by at least:
heating the infiltrated preform at a first temperature, such that the densifying agent disposed in the at least some channels shrinks to form a plurality of interconnected cracks, andexposing the infiltrated preform to an oxidizing agent; and heating the at least partially stabilized preform at a second temperature to carbonize at least the stabilized densifying agent to form a carbonized preform.