The use of carbon fiber as a high-tech material on bicycles is a matter of the last decade. Strictly speaking, carbon fiber is not a simple carbon element, but a mixture of carbon elements bonded and reinforced with epoxy resin after weaving. In the early years of carbon fiber, due to technical reasons, the epoxy resin used would even decompose in the sun. With the advancement of technology, various shortcomings of this excellent material are gradually overcome. For example, the German K frame uses high-quality 16K carbon fiber, which is even stronger than steel and has a quality assurance for life.
Generally speaking, carbon fiber as a bicycle material has the following characteristics:
1. Extremely light weight: Carbon fiber road frames around 1200 grams are already visible everywhere. Since the mass of carbon is only 1.6 g / cm3, it is no longer a dream to make a frame of about 1 kg.
2. Good shock absorption performance. Carbon fiber can effectively absorb shock and maintain good rigidity. This feature makes it a good competition-grade material.
3. Frames of various shapes can be made. Unlike the general manufacturing process of metal frames, carbon fiber frames are generally made with molds first, then carbon fiber sheets are applied to the molds, and finally epoxy resins are used for bonding. This manufacturing process can use aerodynamics to create a frame with minimal wind resistance.
The current shortcomings of this material are mainly the following two points:
1. Complex stress calculation. The carbon fiber frame is composed of carbon fiber, which is characterized by strong tensile strength but weak shear strength. Complex stress calculations (longitudinal rigidity and lateral rigidity) are required during processing, and carbon fiber sheets are formed by overlapping according to the calculations. Generally speaking, the impact resistance of carbon fiber is quite good, but the puncture resistance is very poor. It means that it doesn't matter if you fall horizontally or vertically. You are afraid that you will encounter one or two sharp pebbles during the horizontal and vertical shots. It can't be solved by welding it.
2. The cost is expensive. Compared with the titanium alloy, the price of the carbon fiber frame is unsurpassed. The price of the top carbon fiber frame is tens of thousands, and the price of the C40 and C50 in Conaco is even more than 20,000. yuan. This is mainly because the manufacturing process of carbon fiber frames requires a lot of manual work, and the scrap rate is very high, resulting in a large increase in costs.