An experimental method for evaluation of the localized moisture con tent in graphite epoxy composites or other organic solids is described. The method involves specimen conditioning in D2 O, followed by measurement of the localized deuterium concentration by means of the D ( 3 He, p)4 He nuclear reaction. Equilibrium moisture levels in two epoxy resins and two graphite epoxy composites measured by the nuclear technique are con sistent with those obtained from bulk gravimetric methods. Moisture pro files measured in a unidirectional graphite epoxy composite are compared to predictions from diffusion theory.
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