Flat-knitted spacer fabrics (SF) are used as padding material in protectors, clothes or mattress covers due to their adjustable pressure stability and air permeability. SF consist of two surfaces layers (sl) and a connecting spacer layer. The adjustable distance between the surface layers and the near-net shape production possibility make SF particularly interesting for composite. The SF however, even so the spacer layer are formed by bridges or pile yarns, are not inherently stable immediately after textile production. This requires either a consolidation or using elastic yarn materials in the sl to generate the necessary tension for erecting the pile yarns. Anyway with both method, inherently stable, open knitted fabric structures as cellular distance structures for composites are not realizable.
To extend the use of SF besides the already named areas also for medical applications there is a crucial need for research into the development of solutions to produce staple cellular spacer structures with open net like sl. Consequently, main focus of the research is the development of manufacturing technology and structures based on process-integrated shaping of monofilament or wire yarns during the structure production. Solving these complex tasks requires the development of innovative technological principles for the textile-technical manufacture of cellular spacer structures with compression-rigid spacer area between the surface layers and a surface topography adjusted to the matrix system if necessary. To achieve these aims research activities can be divided into two main points:
1. Research into binding development and materials used for creating innovative, cellular spacer structures (iSF). Main focus is the development of different types of thickness, pressure stability and displacement resistance of conventional SF.
2. Infiltration investigation: The cellular sl are a decisive advantage of these innovative, cellular spacer structures while used in composites, as it enables usage of high viscous matrix systems while ensuring homogeneous infiltration.
One result in this context is a comparison of the productivity between the different SF. The number of carriage strokes for the iSF can be reduced dramatically, which is the main reason for the increase of the productivity. First samples of the innovative cellular iSF already proved successfully the therefore possible knitting time reduction by more than 100%.