The Best Part #2 of CAIB Report

ElleninLosAngeles wrote:

This is interesting. I haven't heard from anyone why reinforced carbon
carbon is supposed to be so amazing in the first place - do you know
what makes it a special material? How is it made? What is it
"reinforced" with? I did find out that it's "specialness" had to do
with its superior ability to withstand HEAT and not necessarily any
superior ability to withstand an impact. Too bad NASA didn't do more
thorough testing

Carbon-carbon is a composite consisting of carbon fibers in a carbon
matrix. It is made by first weaving carbon fibers into the appropriate
shape, then going through a laborious, lengthy process where the
form is filled with some sort of hydrocarbon and then heated to
convert some of that hydrocarbon to carbon + gases. This is repeated
until the porosity is below some specified limit.

The material also has a silicon carbide coating to provide oxidation
resistance, and some TEOS (an organosilicate compound) to renew the
SiC in case of damage.

Paul