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Abstract

This paper presents the results of an investigation to determine the delamination states which develop in a quasi-isotropic [(± 45)₂/O₂/90₂] _s graphite/epoxy laminate with a circu lar hole due to tension-tension loads. The tests were performed at different constant-load amplitudes, and specimens were nondestructively inspected for damage and locations of delamination using a diiodomethane (DIM) enhanced X-ray radiography. Mechanisms of delamination growth were discussed and stiffness reductions due to damage were mea sured. A model for predicting the initiation and locations of delamination along curved edges was presented. Comparison of observed initial delamination locations with pre dicted results shows a good agreement between them.

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Characteristics of Delamination Growth in a Notched Graphite/Epoxy Composite Laminate

Abstract

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