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.

A significant improvement in the properties of plastic components can be achieved by introducing flexible multiaxial textile grids as reinforcement. This reinforcing concept is based on the layerwise bonding of biaxially or multiaxially oriented, completely stretched filaments of high-performance fibers, e.g. glass or carbon, and thermoplastic components, using modified warp knitting techniques. Such pre-consolidated grid-like textiles are particularly suitable for use in injection moulding, since the grid geometry is very robust with respect to flow pressure and temperature on the one hand and possesses an adjustable spacing to enable a complete filling of the mould cavity on the other hand. The development of pre-consolidated textile grids and their further processing into composites form the basis for providing tailored parts with a large number of additional integrated functions like fibrous sensors or electroconductive fibres. Composites reinforced in that way allow new product groups for promising lightweight structures to be opened up in future. The article describes the manufacturing process of this new composite class and their variability regarding reinforcement and function integration. An experimentally based study of the mechanical properties is performed. For this purpose, quasi-static and highly dynamic tensile tests have been carried out as well as impact penetration experiments. The reinforcing potential of the multiaxial grids is demonstrated by means of evaluating drop tower experiments on automotive components. It has been shown that the load-adapted reinforcement enables a significant local or global improvement of the properties of plastic components depending on industrial requirements.

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