The difference between dry forming and wet forming of carbon fiber composites
In the production field of carbon fiber products, there are dry carbon fiber and wet carbon fiber, and this distinction is expressed from the production process of carbon fiber products. The two most commonly used methods for processing carbon fiber composites are prepreg autoclave forming mode and vacuum introduction mode. Due to the difference in the infiltration method during the use of the cloth, there is also a manifestation of dry and wet. Future Composite Materials combines its own experience in carbon fiber to briefly introduce the difference between carbon fiber wet forming and dry forming.
The current mainstream formula of carbon fiber composite materials is carbon fiber and resin composite, and there are two ways to combine these two materials. In the carbon fiber material industry, there is a prepreg that is a combination of resin and fibers. In the industry, the method of using prepreg to process products is called dry molding, and other non-prepreg methods are called wet process. At present, the method of vacuum introducing resin molding is the main method of wet process, and the process of using prepreg autoclave molding is the main performance of dry molding.
The main steps of the vacuum introduction process are to arrange the carbon fiber cloth in the prefabricated mold, and use the vacuum pressure to arrange the resin in the mold to combine with the carbon fiber. This method is fast and low in cost, but the material ratio is difficult to accurately control, and the quality of the product is accurate. Hard to control. Since the prepreg is infiltrated with the resin when the carbon fiber cloth is produced, the combination is better and the proportion control precision is high. After high temperature and high pressure molding, the product quality and precision are higher.
There are obvious differences in the performance of the products produced by the two processes. The wet process is prone to deformation during processing and the truncation part is prone to de-filamentation. The resin and fiber have poor bonding properties, and are prone to oxidative discoloration due to contact with air. The dry prepreg process does not have the above situation, but it is prone to performance degradation under UV irradiation.
The carbon fiber products produced by these two production methods have obvious differences in weight and hardness. In order to distinguish them, they are called wet carbon fiber and dry carbon fiber. Carbon fiber products refer to the use of carbon fiber prepregs as raw materials, which are processed into material products that can meet the requirements of use through different processing methods.
Carbon fiber fittings are "soft on the outside and rigid on the inside". They are lighter than metal aluminum, but stronger than steel, and have the characteristics of corrosion resistance and high modulus. They are important materials in national defense, military industry and civilian use. It not only has the inherent intrinsic properties of carbon materials, but also has the soft processability of textile fibers. It is a new generation of reinforcing fibers. Compared with dry carbon fiber, the carbon fiber pattern of wet carbon fiber will be deformed when it is vacuumed, and carbon fiber filaments will also be seen in its cross section, while dry carbon fiber products will not.
The carbon fiber products made by the dry process have good hardness and are easy to CNC process, but the production cycle is long and it is not easy to mass-produce, and the production cost is high. Carbon fiber products refer to the use of carbon fiber prepregs as raw materials, which are processed into material products that can meet the requirements of use through different processing methods. The cost of wet molding products is low, the production process is relatively simple, and the production efficiency of the process is high. In the current production of carbon fiber, dry forming is mainly used in the case of high precision and high quality requirements, and wet forming is mainly used in appearance parts and mass production.