PURPOSE: To improve shock resistance by impregnating a carbon fiber preform with an org. solvent soln. of a solvent-soluble thermosetting resin having specified mol.wt. as the source material of a carbonaceous matrix, drying the preform, molding, and burning to promote to close pores.
CONSTITUTION: A solvent-soluble thermosetting resin having 1000-30000mol.wt. such as phenol resin used as a carbonaceous matrix constituting source is dissolved in a solvent of high boiling point such as furfuryl alcohol having 150-180°C boiling point to prepare a soln. of specified concn. A two-dimensional nonwoven fabric obtd. by mixing and dispersing carbon fiber such as polyacrylonitrile based one (PAN) of 10-200mm fiber length and carbonized org. fiber of PAN fiber, etc., at 50/90 to 95/5 weight ratio is impregnated with the obtd. soln., treated to remove the solvent, molded, and burned in an N2 gas atmosphere. then the burned body is impregnated with pitch or the like in vacuum, subjected to high pressure impregnation, carbonized, and finally burned to obtain a shock-resistant carbon-carbon composite material having 10-30vol.% closed pore of ≤30μm in a carbonaceous matrix.
NIKAIDO MITSUNOBU
ASHIDA HIDEO
