DEGRADATION OF MULTIPLY POLYMER-MATRIX COMPOSITES INDUCED BY SPACE ENVIRONMENT

In order to simulate the long-term exposure of composite laminates in space, various graphite/epoxy laminate specimens have been subjected t o electron radiation combined with thermal cycling, or to oxygen atom fluxes. The results show that the synergistic action of electrons and thermal cycling degrades the matrix by chain scission, crosslinking an d microcrack damage, altering the composite's properties. The erosion induced by oxygen atoms provokes a decrease in flexural stiffness. Thi s decrease may be drastically amplified for long duration exposure and could limit the service life of. such materials in spacecraft applica tions.