The effect of load train alignment on the fatigue life, remaining strength, and fracture behavior of unidirectional graphite epoxy laminates was studied. Eight-ply, unidirectional graphite/epoxy specimens with a layer of release cloth embedded at the mid plane were examined. The remaining quasi-static strength of specimens containing fatigue damage was relatively unaffected by alignment; however, alignment was found to greatly influence the fatigue life of the specimens, especially at low load levels. Misalignment ef fects are very evident in the S-N diagram of the laminate.
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