MESOPHASE-PITCH FOR LOW PRESSURE CARBON/CARBON COMPOSITE PROCESSING

Some carbon/carbon applications require high composite density, higher than 1.9 or even 2.0. In this later case, a process involving autoclave is necessary for the carbonization step at very high pressure. Pressure increases the carbon yield and suppresses a second drawback, the swelling and rejection of the pitch out of the porosity, especially in the last cycles. A high pressure does allow the carbonization of the precursor to proceed within the porosity without rejection out of the preform : typically 100MPa. A process involving autoclave at high pressure is known as the HIPIC process for Hot Isostatic Pressure Impregnation Carbonization process. In this work an aromatic resin replaces the regular coal tar pitch used with the HIPIC process. The processing is conducted at low pressure and developed for needled fiber preforms. The aim is to test a possible low-cost alternative process (no autoclave) by using a much-sophisticated precursor.