Carbon fiber products are quite common nowadays; from F1 cars, snowboards, motorcycle parts to (ofcourse) bicycle frames. Carbon fiber material comes in a variety of “raw” building-blocks, including yarns, uni-directional, weaves, braids, and several others, which are in turn used to create composite parts.
About carbon fibers
In order to create a composite part, the carbon fibers, which are stiff in tension and compression, need a stable matrix to reside in and maintain their shape. Epoxy resin is an excellent plastic with good compressive and shear properties, and is often used to form this matrix, whereby the carbon fibers provide the reinforcement. Since the epoxy is low density, one is able to create a part that is light weight, but very strong. When fabricating a composite part, a multitude of different processes can be utilized, including wet-layup, vacuum bagging, resin transfer, matched tooling, insert molding, pultrusion, and many other methods. In addition, the selection of the resin allows tailoring for specific properties.
There are lots of different grades of carbon fibers, with different tensile modulus (MSI). Tensile modulus is a measurement of stiffness. But enough talk about carbon. What about the carbon of the future? The lightest, strongest material for the high-end products, for the sports where every second counts!
TeXtreme, the carbon of the future?
Oxeon, a Swedish company developed a way to weave thin unidirectional strips of ultra high modulus carbon fiber in such a way that the finished product leaves very little excess resin. This product is called “TeXtreme”, and it has solved the difficulties that engineers have in most designs that require opposing wraps of unidirectional fibers. The definition for unidirectional is the carbon material has every fiber running parallel.
[zilla_alert style=”green”]The advantages of this type of material is that it leaves a minimal amount of excess resin leftover and therefore can be built into a stronger shape that is lighter in weight [/zilla_alert]
For comparison, woven carbon cloth is made from bundles of loose fibers shaped into yarns and then woven into more conventional fabric that is later liquified with resin. This carbon is called ’3K’ or ’5K’ that gets most utilized in the industry, which cannot be constructed from the strongest carbon because the bending stress of the looms will break the fibers. Additionally each warp creates dead pockets of resin in conventional carbon fabric that adds weight and reduces the objects strength.
Oxeon developed equipment that can form thin tapes with a high fiber density, and those are wove into a `checkerboard` looking pattern that is almost as thin as one layer of UD cloth. This process is the highest strength of all the materials, and its value is saving layup time, and increase impact resistance, and to reduce the weight of ultra-high-strength carbon fiber bike parts.
[zilla_alert style=”green”] The theory behind this ´spread tow fabric´ is quite simple, by arranging the fibres in the woven structure in the straightest orientation possible the fiber properties are used in the most effective way to carry load, both in tensile and compression [/zilla_alert]
TeXtreme Technology explained:
1. The Spread Tow structure makes it possible to achieve thinner laminates.
2. Straighter fibers with reduced crimp optimize and strenghten the composite.
3. Lower crimp reduce the amount of excess plastic thereby minimizing weight and creating a smoother surface.
The fibers are holding their +-45 degree position really well during the wet layup process, making it great to work with. In our eyes TeXtrme is the high-end material of the future, creating the best and lightest carbon fiber sport products.
