A novel processing solution for the production of spatial three-dimensional stitch-bonded fabrics

Abstract

Spatial three-dimensional (3D) stitch-bonded preforms offer a huge potential and an optimal utilization of the fiber mechanical properties for their usage in various technical applications. These preforms form an efficient alternative to the existing two-dimensional textile preforms due to their load-bearing fiber orientation offered by their geometrical configuration. The fundament of this research activity, based on the stitch-bonded technology, is the development of a new processing solution for producing 3D spatial open stitch-bonded textile preforms with minimal processing stages. Based on a newly developed concept with variable warp yarn delivery and differential doffing, this technology is principally enhanced so that various helical, circular and curved grid structures, along with 3D spatial structures, could be produced on a single machine with minimal setup, which hitherto has not been realized with any other existing processing technique. These novel form-based textile preforms are found to be suitable for application as reinforced components in complex spatial composites with a mineral or a plastic-based matrix, wooden composites and elastomers.

3D Textiles Based on Warp Knitted Fabrics: A Review

“…Since NCF made from high-performance fibres, such as carbon or glass, have only a low material ductility, even relatively low draping forces lead to large displacements of the yarn layers. A promising approach to compensate for the different draping forces in NCF is to give each yarn a pre-defined individual length based on the final three-dimensional shape in the draped state, hereafter referred to as the yarn reserve [ 31 , 32 , 33 , 42 , 43 , 61 ]. These yarn reserves may be unevenly distributed over the yarn laid down (inhomogeneous yarn reserve) or evenly distributed over the length of yarn laid down (homogeneous yarn reserve).…”

“…Fundamental research activities by Sankaran et al led to the development of curved reinforcing grids that can be specifically adapted to geometric shapes through variable single warp yarn delivery [ 63 ]. The application of this technological approach is limited to simple 3D contours.…”

Textile reinforcement structures for concrete construction applications––a review

“…208 Based on such bi-and multiaxial grid-like NCFs, Sankaran et al developed a numerically controlled delivery and doffing system for the multiaxial warp-knitting technology to produce grids with variable warp yarn lengths, which enables the production of 2D reinforcement textiles adapted for specific curved 3D shapes, such as the shells of a pavilion. 74,[209][210][211] Spacer fabrics. Warp-knit spacer fabrics are produced using double-bar raschel machines producing two layers of a warp-knit textile connected by spacer yarns.…”

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

“…Multiaxial warp-knitting (stitch-bonding) technology is an extremely productive technology in terms of the quantity and quality of fabrics produced [18]. Research activity in this field of technology has been carried out to realise an optimal and precise fiber placement through yarn manipulation in accordance to the load distribution [19,20]. The initial work on warp yarn manipulation technology at the Institute of Textile Machinery and High Performance Technology, Technische Universita¨t Dresden dates back to 1986 where controllers for warp yarns were first developed for the warp-knitting machine Malimo 14016 [21].…”