A model for the conslidationof thermoplastic composites reinforced with a warpknitted fabric was developed. The evolutionof void content during composite consolidation achieved via film stacking was related to the procesing parameters and the amterial properties. Since the knitting process results in local variations of fiber volume fractions even within a tow, the flow mechanisms are not identical to those occurring inhomogeneously dispersed fibers. Two different types of micro-scale porosities were determined and a unit cell geometry was proposed for modeling. The reduction of the effective pressure due to the gas entrapment was also accounted for. Predictions of the variation of the void content as a functionof time, pressure and temperature were dompared to experimental data. As a good correlation was found between experiments and predictions, this approach can thus be applied to the consolidation of textile reinforcements in which the tows are locally compressed.
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