Effect of ionizing radiation on the mechanical and structural properties of graphite fiber reinforced composites

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1982

OSTI ID:6534915

Wolf, K W

It is widely known that graphite fiber composites have many properties which make them attractive candidates for aerospace applications. Therefore, it is important to determine the effects of ionizing radiation on composite integrity, particularly ultimate stress and modulus. T300/5208 (graphite/epoxy) and C6000/PMR 15 (graphite/polymide) composites were exposed to various levels of 0.5 MeV electron radiation with the maximum dose being 10,000 Mrad. A three-point bending test was used to evaluate the ultimate stress and modulus of the composites. In all composites except transverse samples of C6000/PMR 15, ultimate stress values remained approximately constant or increased slightly. The modulus values remained approximately constant for all composite types regardless of the radiation level. In an effort to more fully understand these results, the emphasis of the investigation was focused on interfacial aspects of composites. Interlaminar shear tests were performed on T300/5208 and C6000/PMR 15 composites irradiated to 10,000 Mrad. There was an initial increase in interlaminar shear strength (up to 1000 Mrad) followed by a sharp decrease with further radiation exposure. Using scanning electron microscopy, no visual differences in the mode of fracture could be detected between ruptured control samples and those exposed to various levels of radiation. Electron spectroscopy for chemical analysis (ESCA) revealed little change in the surface elements present in control and highly irradiated T300/5208 composite samples.

• OSTI ID: 6534915
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360306* -- Composite Materials-- Radiation Effects-- (-1987)
360400 -- Polymers & Plastics-- (-1987)
CARBON
COMPOSITE MATERIALS
ELECTRONS
ELEMENTAL MINERALS
ELEMENTARY PARTICLES
ELEMENTS
EPOXIDES
FERMIONS
FIBERS
GRAPHITE
LEPTONS
MATERIALS
MINERALS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
STRESSES