Accession Number : ADA301814

Title :   Mesophase Behavior Fundamental to the Processing of Carbon-Carbon Composites.

Descriptive Note : Interim technical rept. 1 Oct 94-30 Sep 85,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS

Personal Author(s) : White, J. L. ; Sheaffer, P. M.

PDF Url : ADA301814

Report Date : 03 JUN 1986

Pagination or Media Count : 54

Abstract : The behavior of the carbonaceous mesophase under conditions of composite fabrication has been investigated to understand (1) the formation of microstructure within the fiber matrix, (2) the mechanisms that determine process efficiency, and (3) how the properties of the matrix are affected by carbonizing and graphitizing heat treatments. Experimental work in FY 85 focused on two concepts to introduce new approaches to fabrication: pressure cycling, while the mesophase is still plastic, to attain more complete impregnation; and oxidation stabilization, to circumvent the inefficiencies of thermal hardening caused by blowout of the mesophase matrix by gaseous pyrolysis products. Other experimental work included observations of the microstructural mechanisms operating in the mesophase matrix during heat treatment beyond the point of mesophase hardening. (MM)

Descriptors :   *FIBER REINFORCED COMPOSITES, *CARBON CARBON COMPOSITES, *OXIDATION, STABILIZATION, THERMAL PROPERTIES, MICROSTRUCTURE, PROCESSING, COMPOSITE MATERIALS, DEFORMATION, FABRICATION, MATRIX MATERIALS, FRACTURE(MECHANICS), PHASE, HEAT TREATMENT, BUBBLES, FILAMENTS, PRESSURIZATION, GRAPHITED MATERIALS, HARDENING, PLASTICS, PORE PRESSURE, ELONGATION, PYROLYSIS, DRAWING(FORMING), SHRINKAGE, IMPREGNATION, THERMOGRAVIMETRIC ANALYSIS.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE