Low degree of homogeneity due to phase shifts for woven composites

In this study, variation of effective properties due to fiber tow phase shi fts was investigated for woven textile composites. Plain weave unit cells w ere modeled with randomly selected phase shifts. Effective properties were calculated using macro finite elements and the results were assessed statis tically. It was found that the effective properties depended strongly on th e tow phase shifts for thin plain weave composites. The variation in the ef fective modulus and Poisson's ratio was large, and it showed skewed distrib utions. As the number of layers increased, however, the average properties converged and the coefficient of variation decreased.