Characterization of the Effective Elastic Modulus of an Integrated Sandwich Composite

Abstract

In this paper, an integrated sandwich composite adopting 3-D woven fabrics as the core material is thoroughly studied for its effective elastic modulus. In spite of the extensive applications of 3-D woven sandwich composites due to their improved mechanical properties, no suitable theoretical model has been proposed to predict the elastic modulus for such composite structures in the open literature so far. For the present work, a theoretical model by means of a micromechanics approach and the rule of mixtures is proposed to predict its effective in-plane elastic modulus. To verify the veracity of our prediction, unidirectional tensile tests were also carried out to determine the effective elastic modulus. Eventually, our experimental results turn out to agree with our prediction very well.

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