Effects of cure temperature, electron radiation, and thermal cycling on P75/930 composites

Technical Report · Sat Dec 01 04:00:00 EST 1990

OSTI ID:6065936

Funk, J G

Graphite/epoxy composites are candidates for future space structures due to high stiffness and dimensional stability requirements of these structures. Typical graphite/epoxy composites are brittle and have high residual stresses which often result in microcracking during the thermal cycling typical of the space environment. Composite materials used in geosynchronous orbit applications will also be exposed to high levels of radiation. The purpose of the present study was to determine the effects of cure temperature and radiation exposure on the shear strength and thermal cycling-induced microcrack density of a high modulus, 275 F cure epoxy, P75/930. The results from the P75/930 are compared to previously reported data on P75/934 and T300/934 where 934 is a standard 350 F cure epoxy. The results of this study reveal that P75/930 is significantly degraded by total doses of electron radiation greater than 10(exp 8) rads and by thermally cycling between -250 F and 150 F. The P75/930 did not have improved microcrack resistance over the P75/934, and the 930 resin system appears to be more sensitive to electron radiation-induced degradation than the 934 resin system.

• Research Organization: National Aeronautics and Space Administration, Hampton, VA (USA). Langley Research Center
• OSTI ID: 6065936
• Report Number(s): N-91-15332; NASA-TM--102712; NAS--1.15:102712
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
BEAMS
BRITTLENESS
CARBON
COMPOSITE MATERIALS
CURING
ELECTRON BEAMS
ELEMENTAL MINERALS
ELEMENTS
EPOXIDES
GRAPHITE
LEPTON BEAMS
MATERIALS
MECHANICAL PROPERTIES
MINERALS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PARTICLE BEAMS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
SHEAR PROPERTIES
STABILITY
TEMPERATURE EFFECTS
THERMAL CYCLING
THERMAL DEGRADATION