How is carbon fiber braided

Technical University Dresden Knitting with carbon

According to the scientists at the Technical University of Dresden, the materials of the future should be one thing above all else: as light and at the same time as stable as possible. That is why they are researching so-called lightweight materials. They are particularly concerned with a high-tech material: carbon fiber as the basis for the new materials. This will later be used to create houses that are much more durable than reinforced concrete structures. But also cars, bicycles and airplanes, some of which are already using this technology today.

Carbon fibers are industrially manufactured fibers made from carbon-containing raw materials that are chemically treated. They are considered to be particularly firm and stable. A carbon fiber has a diameter of about 5-9 micrometers. They are combined and processed into fabrics, scrims or braids. The fibers are mainly used for the production of carbon fiber reinforced plastic.

The idea behind the composite materials is thousands of years old. Theoretically, a clay-straw mixture from which huts are built is also part of it - but has practically nothing to do with the lightweight construction materials that are produced at the Institute for Lightweight Construction and Polymer Technology at TU Dresden. It is about so-called fiber composites. In principle, these always consist of two components: a matrix - such as concrete - and a reinforcement or reinforcement structure - such as steel or carbon. The reinforcement bears the loads and absorbs tensile and compressive stress. The matrix embeds the reinforcement - it is virtually enclosed by the matrix. It protects the reinforcement from environmental influences, makes it dimensionally stable - otherwise steel or carbon would bend - and distributes the force evenly.

Lightweight construction for our everyday life

But for carbon to be used as reinforcement, the fibers must first be brought into a shape that can be enclosed by concrete or plastic. The scientists use their high-speed radial braiding system for this purpose. With their help, a braided reinforcement structure is created from the carbon fibers. It is braided around a hollow body. For example, a fiber composite tube can be created by first braiding the reinforcement structure on the braiding wheel. This is then later combined with a matrix, for example a synthetic resin. Similar lightweight hollow structures are used in bicycle frames, tanks, sometimes cars and, above all, in modern aircraft. Because the lightweight construction with carbon fiber reinforced plastic is comparatively expensive. The researchers at the TU Dresden are working on changing that.

- System at the Institute for Lightweight Construction and Polymer Technology at the Technical University of Dresden
- Braided wheel size around seven meters
- 288 clappers
- enables overbraiding of component cores with fiber composite structures with a diameter of up to 4.20 meters and a length of up to 28 meters
- allows overbraiding with carbon or fiberglass