The effect of nesting on the in‐plane permeability of unidirectional fabrics in resin transfer molding

Abstract

The nesting of layers has great effect on the permeability, which is a key parameter in resin transfer molding. In this article, two mathematical models were developed to predict the in-plane permeability of unidirectional fabrics with minimum and maximum nesting, respectively. For different zones of characteristic yarn arrangement in the unit cell, the local permeability was modeled as a function of geometrical yarn parameters. The global permeability was then modeled as a mixture of permeabilities of different zones with the electrical resistance analogy. A reasonably good agreement was found between the model predictions and experimental results. We also found that at the same fiber volume fraction, the results for Ky were two times larger with minimum nesting than with maximum nesting, whereas the results for Kx were a little lower with minimum nesting than maximum nesting. In addition, the differences between minimum and maximum nesting decreased with increasing fiber volume fraction. POLYM. COMPOS., 37:1695-1704, 2016

Compaction behavior of 3D woven preforms with hybrid fibers and under different process parameters

“…In addition, the degree of compaction between layers has an important influence on the subsequent liquid impregnation molding. [3,4] Wei et al discussed the influence of binder content and process parameters on the preforming behaviors of woven and knitted fabrics. [5][6][7] Li [8] and Yang et al [9] investigated the compressive properties of carbon fiber and glass fiber fabrics during liquid composite molding.…”

In-Plane Permeability Model of 0°/90° Non-crimp Fabrics in Resin Transfer Molding

“…And the in-plane permeability was then obtained by following Chan and Hwang's method [8]. More detailed explanation is given in the study [5].…”

“…To possess a comprehensive understanding, theoretical models for permeability prediction are worth performing. In our past studies [5], the permeabilities of unidirectional fabrics have been modeled with the electrical resistance analogy. In the reference [6], the out-of-plane permeability of 0°/90° non-crimp fabrics also has been studied with the same method.…”

Out-of-plane permeability of multilayer 0°/90° non-crimp fabrics

“…Although some models were proposed considering the effect of layer shift on permeability, the layer shift must be given in advance to predict the permeability [7][8][9]. In fact, obtaining the information about shift between each layer is very difficult.…”