A Micromechanics Model for the Effective Young's Modulus of a Piecewise-Isotropic Laminate with Wavy Patterns

Abstract

A mathematical model based on the Euler-Bernoulli beam theory is proposed for pre dicting the effective Young's moduli of piece-wise isotropic composite laminates with wavy patterns in the main load-carrying layers. Strains in corrugated layers, in-phase layers, and out-of-phase layers are predicted for various geometries and material configurations by assuming matrix layers as elastic foundations. Experimental results obtained from cor rugated aluminum specimens and aluminum/epoxy specimens with in-phase and out-of- phase wavy patterns coincide very well with the predictions.

The work represents a preliminary effort toward further generalization of the model for two-dimensional anisotropic laminates containing wavy patterns in the main load-carrying layers.

Keywords

wavy layer wrinkled fiber effective Young's modulus corrugated layer in- phase out-of-phase pseudo strain.

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