Metallurgist, Aero Materials Laboratory, Naval Air Development Center, Warminster, Pa.
Materials engineer, Naval Air Systems Command, Washington, D.C.,
Pages: 18 Published: Jan 1976
Natural weathering of selected graphite/epoxy composite materials has been studied primarily by measuring specific mechanical properties. Commercially available composite prepregs were fabricated into panels and exposed at Warminster, Pa., and Canal Zone, Panama. Principal mechanical property determinations used to assess degradation were tension, compression, and short-beam shear tests.
The T400/2544 panels were severely degraded after 18 months of exposure in Panama. Pronounced warping, loose fibers, and loss of resin were very much evident with this material.
Shear data taken from Panama exposures showed that the use of a coating system on the panels was extremely beneficial.
To data, the Modulite 5208 composite system has shown the least variability in measured mechanical properties with increasing exposure time.
composite materials, weathering, mechanical properties, degradation, environmental tests, resins, matrices
Paper ID: STP27781S