Evaluation of Composite Curing Stresses
A recently developed approach to predict the initial stress field within a composite laminate after fabrication processing is examined in some detail. In this approach, the material response is assumed to be elastic with temperature-dependent properties. With the introduction of the concept of a stress-free temperature, it is shown that this position is defensible by use of deformation measurements on unsymmetric angle-ply units. Implications concerning the influence of the curing stress field on initial damage level (first-ply failure) are studied analytically. The predictions indicate a marked effect of curing stress in certain laminates. The consequences of combined moisture and thermal effects on initial damage level also are discussed.
Key Wordscomposite materials laminates stresses deformation measurement residual stress
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