The carbon fiber composite can be molded as a whole through reasonable design, which can save a lot of combination and assembly frames and reduce the production cost. With the development of technology, in civil carbon fiber products, professional sports equipment is a more extensive and mature field of carbon fiber application. At present, there are many molding methods of carbon fiber materials for sports equipment, mainly including winding molding, molding, RTM molding, pultrusion molding and so on.
1. Winding Process
In a special winding machine, the prepreg blank is evenly and regularly wound on a rotating mandrel, and the products are obtained by curing and removing the core mold. The winding method is not only suitable for manufacturing simple rotating bodies, such as cylinders, spheres and some positive curvature revolving bodies or cylinder shaped products, but also can be used for manufacturing non rotating parts.
Its remarkable feature is that the fiber can be arranged according to the stress situation of the product, so as to give full play to the strength of the fiber and obtain light and high-strength products; in the process, it can realize continuous and mechanized production, and the production cycle is short, the production efficiency is high, and the labor intensity is low; the disadvantage is that the core mold needs to be removed after the product is solidified, which is not suitable for the manufacturing of products with concave surface 。 Golf clubs and fishing rods can be made in this way.
2. Molding Process
Molding process is a method of forming composite products by heating and pressure curing in a closed mold cavity. The mould is composed of two parts: male and female. The reinforced materials are short cut fiber felt, continuous fiber felt and fabric.
The molding method has the advantages of high production efficiency, accurate product size and smooth surface. It is especially suitable for manufacturing large quantities of products with high precision and repeatability requirements. The products with complex structure can be formed at one time without any auxiliary processing (such as turning, milling, planing, grinding, drilling, etc.) that may damage the performance of the products, and the appearance and size of the products are repeatable. Its disadvantages are: complex mold design and manufacturing, high initial investment, easy to be limited by equipment.
3. RTM Process
RTM (resin transfer molding, referred to as RTM) is a common molding technology for composite materials. The technology is that the fiber or preform is placed in the closed mold cavity, and the resin solution is injected into the mold cavity with pressure to soak the fiber or preform, then solidify and demould the products.
The advantages of RTM technology are: it can manufacture complex composite components with high quality, high precision, low porosity and high fiber content, and smooth double surface can be obtained without gel coat resin; the time from design to production is short and the production efficiency is high; RTM Mold and product can be designed by CAD, mold manufacturing is easy, and material selection is wide.
The components and pipe fittings formed by RTM are easy to realize local reinforcement or manufacture locally thickened components, and the composite materials with core materials can be formed at one time; the volatilization during RTM molding is less, which is conducive to the protection of workers and production environment. At present, RTM technology is generally used to mass produce the body parts of bicycles and rowing boats.
4. Pultrusion Process
For continuous production of fiber composite profiles. Pultrusion is a method of making linear products with specific cross-section shape and length unlimited by dipping, extruding, heating curing and cutting under external force.
It will be impregnated continuous fiber through a certain cross-section shape of the mold, in the mold cavity curing or molding in the cavity gel, mold heating and curing, pulling force under the pulling force can continuously pull out the endless profile products. The results show that the pultrusion process is simple and the efficiency is high; when the products are prepared by pultrusion, the reinforced fibers are arranged in parallel along the axial direction, so the strength can be effectively utilized.
Isotropic products can be prepared by using fiber felt reinforced materials, and the transverse strength of products can be improved by using braided tape. Pultrusion products have the characteristics of high strength, light weight, easy decoration and good surface quality. These properties are ideal for many types of sports facilities and related applications, such as fishing rod, bow and arrow, pole pole, ski pole, etc.
The rapid development of modern science and technology has an unprecedented impact on sports. Today’s world sports competition is essentially a competition of science and technology, and advanced and novel materials are one of the important conditions to improve the level of sports science and technology. Nowadays, in many sports events, people’s physical and mental stimulation has almost reached the limit, and the victory or defeat is often only in a fraction of a percent. It is difficult to win by relying on strong muscles and good competitive state. Athletes increasingly rely on the wisdom of scientists. Behind the competition between athletes and athletes, there is a comprehensive competition between national scientific and Technological Development and the cohesion of people’s hearts.