Influence of Tow Architecture on Compaction and Nesting in Textile Preforms

Abstract

Transverse compression response of tows during processes such as vacuum infusion or autoclave curing has significant influence on resin permeability in fabrics as well as the laminate thickness, fibre volume fraction and tow orientations in the finished composite. This paper reports macro -scale deformations in dry fibre assemblies due to transverse compaction. In this study, influence of weave geometry and the presence of interlacements or stitches on the ply-level compaction as well as nesting have been investigated. 2D woven fabrics with a variety of interlacement patterns -plain, twill and sateen-as well as stitched Non-crimp (NCF) fabrics have been investigated for macro-level deformations. Compression response of single layer and multilayer stacks has been studied as a function of external pressure in order to establish nesting behaviour. It appears that the degree of individual ply compaction and degree of nesting between the plies are influenced by tow architectures. Inter-tow spacing and stitching thread thickness appears to influence the degree of nesting in non-crimp fabrics.

Determining the Damage and Failure Behaviour of Textile Reinforced Composites under Combined In-Plane and Out-of-Plane Loading

“…All three ECC TM -style fabrics are woven from a TENAX R HTA 40 3K (200 tex, Heinsberg, Germany) yarn, but in a different setting. Consequently the weight of each specific textile reinforcement will increase, thus the ondulation will increase and the nesting behaviour will change [25,26]. The yarn consists of 3000 (3k) filaments, which are characterised by a high tenacity (HT).…”

“…Especially textile reinforced composites in particular fabric, reinforced composites reveal a high inherent distribution of their geometric features-e.g., ondulation. Furthermore the textile architecture particularly ondulation affects the arrangement and vice versa [25,59]. Hence the data of the advanced analysis method presented in [26] were suitable to derive essential geometric parameters.…”

“…For the determination of the influence of the inner structure, such as ondulation and nesting three plain-weave, fabrics with increasing areal weight have been considered. For comparability, equal weft and fill yarns have been chosen It was found that by increasing areal weight, the ondulation increases, thus so does the nesting effects change [25]. Based on the analysis of the compaction behaviour of the dry textile layers by in situ computer tomography [26][27][28] and image analysis of micrographs, profound knowledge of the geometry and arrangement of the textile reinforcements on meso-scale could be obtained.…”

Liquid composite molding reproducibility in real-world production of fiber reinforced polymeric composites: a review of challenges and solutions

“…An immediate result is the reduction in the compaction levels per individual preform thickness. Yousaf et al [23] found that the thickness of a 6-layer woven preform with nesting under typical compaction is 12% lower than the thickness at the same compaction without nesting. The tow displacement induced by nesting changes randomly local permeability and flow patterns.…”

Compaction Behavior of 0°/90° Non-crimp Fabrics

“…The preforms were usually compacted in a large degree in order to obtain higher fiber volume fractions. Compaction behaviors of fabrics not only determine the final thickness of products, but also affect the geometrical features of fabrics [4][5][6]. Studying the compaction behavior of fabrics is therefore very important to determine processing parameter windows and predict mechanical performance.…”