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Abstract

Moiré interferometry is an experimental technique that is being viewed favorably for verifying analytical predictions of mechanical performance in composite materials. However, since interferometry measures displacements at a free surface, one must separate the effects due to fiber architecture from those due to free-edge effects. This paper addresses the influence of in-plane fiber misalignment on free-edge interlaminar shear strain. Experimental results for laminates with intentional fiber misalignment are compared to analytical predictions by using the finite element method. Small degrees of fiber misalignment are shown to produce large free-edge interlaminar shear strains. Thus, moiré interferometry results may not be quantifiable for nonidealized composites which exhibit in-plane fiber misalignment.

Keywords

composite materials moiré interferometry free-edge shear strain in-plane fiber misalignment

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References

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Influence of In-Plane Fiber Misalignment on Moiré Interferometry Results

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