The strength of individual carbon fibers was measured, and the results were used to calculate the lower bound of strength expected from carbon- fiber reinforced epoxy matrix materials. Using the value of the mean stress in the fibers at fracture of a composite and the principles of linear elastic fracture mechanics, the strength of coupon specimens containing edge slots could be predicted. However, the results of some initial compliance experi ments indicated that some slight modifications of the expressions generated for isotropic pin-loaded specimens were necessary to account for the specific experimental techniques used.
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