Forming process of carbon fiber tube in carbon fiber mold

Carbon fiber, also known as graphite fiber, carbon graphite, referred to as CF (Carbon Fiber). It is a microcrystalline graphite material obtained by piling up organic fibers such as flake graphite microcrystals along the fiber axial direction, and undergoing carbonization and graphitization treatments. Carbon fiber is used in places where mechanical properties need to be improved, and can be combined with resin, ceramic, metal and other composite materials. We usually say CFRP, Carbon Fiber Reinforced Plastic, which is a composite material of carbon fiber and resin, and it is also carbon fiber in a narrow sense.

Because of its light weight, good safety, high mechanical strength and impact resistance, carbon fiber materials are increasingly used in the aviation field, such as commercial airliners, helicopters, and rockets. The carbon fiber mold molding process needs to be heated first, use a mold temperature machine to preheat the mold, then put the prepreg and resin into the mold, and continue to heat up after the mold is closed. After the mixture is fully reacted and solidified, it will be kept warm for a period of time after reaching the highest molding temperature. The first stage is the key to carbon fiber molding, and the temperature must be accurately controlled. In order to prevent the material from shrinking and warping after molding, it is necessary to cool the mold through the cooling system of the mold temperature machine.

In carbon fiber molds, there are many ways to shape carbon fiber tubes, such as hand lay-up, pultrusion, compression molding, and winding.

1. Hand lay-up method. Laminate the dipped carbon fiber sheets in a shear shape, or brush the resin on one side of the layer, and then heat and press it to form. This method can choose the direction, size and thickness of the fiber at will, and is widely used. Note that the shape of the layer is smaller than the shape of the mold, so that the fibers will not bend when pressed in the mold. Today, when the carbon fiber mold preparation technology is highly developed, the hand lay-up process is still widely used in many fields such as petrochemical containers, storage tanks, and automobile shells due to its advantages of simple process, low investment, and wide application.
2. The pultrusion method. The carbon fiber tow material completely infiltrated with the resin is squeezed to remove the resin and air by traction, and then cured in a furnace to form. This method is simple and suitable for preparing rod-shaped and tubular parts. It can realize the automation of the carbon fiber mold production process, and the production efficiency is high.
3. Molding method. This method is to stack the carbon fiber prepreg and put it into a metal mold, pressurize it to overflow the excess glue, and then solidify it at high temperature. After the film is released, the finished carbon fiber mold will come out. This method is most suitable for use. Make car parts. This carbon fiber mold molding technology has the advantages of high efficiency, good part quality, high dimensional accuracy, and low environmental impact. It is suitable for the molding of batches and high-strength composite parts.
4. Winding forming method. The carbon fiber monofilament is wound on the carbon fiber shaft, and then heated and solidified to become a carbon fiber mold product. Carbon fiber winding molding can give full play to its characteristics of high specific strength, high specific modulus and low density. The product has a single structure and can be used to manufacture cylinders, spheres and certain positive curvature revolutions or cylindrical carbon fiber mold products.
Carbon fiber molds have many uses in life. Some of the common uses are: aerospace beams and spars, structural components of Formula One, arrow shafts, bicycle tubes, kayak paddles.