After some recent discussions about nozzle materials and thinking back
to a class I had in university, I was wondering how to make
carbon-carbon composites, and whether this is feasible for
amateurs/hobbyists.
From what I understand (having read the Wikipedia article ;-), first a
carbon fiber reinforced part is made in the classic way.
Then the part is pyrolyzed, i. e. heated in the absence of oxygen such
that the matrix decomposes and the volatile parts evaporate to leave a
pure carbon matrix.
Since the matrix is now very porous, a gas like acetylene has to be
passed through the part so the pores will be filled with carbon.
So I have a couple of questions:
1. Which resin can be used to manufacture the original CFRP part? Epoxy?
Phenolic? Anything?
2. Is there really the need for additional "carbonization" after
pyrolysis if I want to use it as a combustion chamber or a nozzle?
3. Are there any other big obstacles I haven't thought of?
Pyrolysis shouldn't be too hard using e. g. a steel container and a CO2
atmosphere at maybe 1000 °C?
Oliver