A multiaxial warp knitting based yarn path manipulation technology for the production of bionic-inspired multifunctional textile reinforcements in lightweight composites

Abstract

Composites have now revolutionized most industries, like aerospace, marine, electrical, transportation, and have proved to be a worthy alternative to other traditional materials. However for a further comprehensive usage, the tailorability of hybrid composites according to the specific application needs on a large-scale production basis is required. In this regard, one of the major fundamental research fields here involves a technology development based on the multiaxial warp-knitting technique for the production of bionic-inspired and application-specific textile preforms that are force compliant and exhibit multi-material design. This article presents a newly developed yarn (warp) path manipulation unit for multiaxial warp-knitting machines that enables a targeted production of customized textile preforms with the above characteristics. The technological development cycle and their experimental validation to demonstrate the feasibility of new technology through production of some patterns for different field of applications are then discussed.

Development of a highly various warp yarn manipulation system for the fabrication of 2D net-shape non-crimp-fabrics for highly material efficient concrete reinforcements

“…Therefor past research activities focused on the development of additional, modular systems to enhance the multiaxial warp knitting technology such as additional yarn feeding systems, 19 impregnation and consolidation systems, 20 profiling systems, 9,10,21 shaping systems 22,23 and yarn manipulation systems. 24 In order to produce net-shape NCF for concrete reinforcements focus of this study will be on yarn manipulation systems with an outlook on shaping systems. In order to productively manufacture specific textile reinforcements structures using the multiaxial warp knitting technology first yarn manipulation systems have been developed, that allow the realization of customized grid-like structures with a structural and functional integration according to the force direction and formation of the component.…”

“…In order to productively manufacture specific textile reinforcements structures using the multiaxial warp knitting technology first yarn manipulation systems have been developed, that allow the realization of customized grid-like structures with a structural and functional integration according to the force direction and formation of the component. 15,[24][25][26] A first warp yarn manipulation system for functional integration, which allows the limited manipulation of parallel warp yarns, was developed at the Institute of Textile Machinery and High Performance Material Technology (ITM) (Figure 2(b)). 24,25 Hereby, manipulation width and degree of movement are restricted.…”

“…15,[24][25][26] A first warp yarn manipulation system for functional integration, which allows the limited manipulation of parallel warp yarns, was developed at the Institute of Textile Machinery and High Performance Material Technology (ITM) (Figure 2(b)). 24,25 Hereby, manipulation width and degree of movement are restricted. For further variation of the warp yarn path, Cetex GmbH (Chemnitz, Germany) and Karl Mayer Technische Textilien GmbH (Chemnitz, Germany) developed the Variolay Technology, enabling a parallel manipulation of pre-fed warp yarns in a short distance to the warp knitting unit by fixating them on the closed NCF or base fabric (Figure 3(a)).…”

“…Therefor past research activities focused on the development of additional, modular systems to enhance the multiaxial warp knitting technology such as additional yarn feeding systems, 19 impregnation and consolidation systems, 20 profiling systems, 9,10,21 shaping systems 22,23 and yarn manipulation systems. 24 In order to produce net-shape NCF for concrete reinforcements focus of this study will be on yarn manipulation systems with an outlook on shaping systems.…”

Development of multiaxial warp knitting technology for production of three-dimensional near net shape shell preforms

“…The producible textile constructions required for the final geometry are determined by computation of the yarn lengths based on their courses and processing constraints. 16–18 The computed lengths can then be transformed into the machine data, thereby significantly reducing the change time required for the production of different structures. A universal computational principle based on profile segmentation and yarn distribution enables one to calculate the optimal yarn length.…”