Preparation process of carbon fiber composites (Part 2)
Content cohesion(Preparation process of carbon fiber composites (Part 1))
3. Composite of carbon fiber and resin matrix The composite of carbon fiber and resin matrix is a key step in the preparation of carbon fiber composite materials, which directly affects the performance and quality of composite materials. There are many kinds of composite methods, such as hand paste method, spray method, molding method, winding method, etc. Among them, the hand paste method is one of the simplest and most commonly used methods. The hand paste method is to lay the pre-treated carbon fiber and resin matrix on the mold layer by layer, and flatten it with a scraper or brush to eliminate bubbles. Each layer needs to be cured in order for the resin to cure to form a hard layer. Repeat this several times until the desired thickness is reached. Finally, the mold is removed from the composite material and trimmed and processed.
4. Curing of carbon fiber composite materials The curing of carbon fiber composite materials refers to the curing reaction of the composite material at a certain temperature and time, so that the resin matrix forms a hard three-dimensional network structure. Curing conditions depend on factors such as the type and proportion of resin matrix and curing agent used, as well as the thickness and shape of the composite. Generally speaking, the temperature of curing is 120-180°C and the time is 1-2 hours. In the curing process, it is necessary to control the temperature and time to avoid the phenomenon of over-curing or under-curing. Overcuring will cause the resin matrix to become brittle and reduce the mechanical properties of the composite. Undercuring results in incomplete curing of the resin matrix, which affects the stability and durability of the composite.
5. Post-treatment of carbon fiber composites The post-treatment of carbon fiber composites refers to the further processing and modification of the cured composite materials to improve their appearance and performance. There are many methods of post-treatment, such as grinding, polishing, cutting, drilling, painting, etc. Among them, grinding and polishing is one of the most common methods.
Grinding and polishing is the process of sanding the surface of a composite material by using sandpaper or polishing cloth to remove burrs, blemishes and stains from its surface and to improve its surface gloss. The order of grinding and polishing is usually rough grinding, medium grinding, fine grinding and polishing. In the grinding and polishing process, it is necessary to control the pressure and speed to avoid damage to the composite material.
These are the main steps of the preparation process of carbon fiber composite materials. Through these steps, carbon fiber composites with high strength, high modulus, low density, corrosion resistance, fatigue resistance and other advantages can be prepared, which are widely used in aerospace, automotive, sports equipment and other fields.