The compression molding process is a process in which a certain amount of prepreg is placed into the mold cavity of a metal mold, and a press with a heat source is used to generate a certain temperature and pressure. After the mold is closed, the prepreg is heated, softened, compressed, filled, filled, molded, and cured in the mold cavity under a certain temperature and pressure effect, and then a composite material product is obtained.
The characteristic of the compression molding process is the need for heating during the molding process. The purpose of heating is to soften the pre impregnated resin, fill the mold cavity, and accelerate the curing reaction of the resin matrix material. During the process of filling the mold cavity with prepreg, not only does the resin matrix move, but the reinforcement material also moves accordingly. The resin matrix and reinforcement fibers fill all parts of the mold cavity together. As long as the resin matrix has a high viscosity and strong adhesion, it can move together with the reinforcing fibers. Therefore, the molding pressure required for the molding process is relatively high, which requires the metal mold to have high strength, high precision, and corrosion resistance. It also requires the use of a dedicated hot press machine to control the process parameters such as temperature, pressure, and insulation time for curing and molding.
The difference between compression molding and hot press can molding is that compression molding does not require pre impregnated blanks and tooling molds to be placed inside the can body like in hot press can molding. It has outstanding observability and a large scale of pressure regulation. The internal quality of the structure is easy to ensure, and the accuracy of the external dimensions is high. Therefore, it is widely used in the production of composite structural components with messy surfaces. Such as composite data engine blade compression molding.
The compression molding method has high production power, precise product size, and smooth appearance, especially for composite material products with disorderly structures, which can generally be molded in one go without damaging the functionality of the composite material products. The primary deficiency is that the mold planning and production are relatively chaotic, and the initial investment is relatively large. Although the compression molding process has the above-mentioned shortcomings, the mold molding process still occupies an important position in the composite material molding process.
Article source: SMC insulation board processing - Jiangmen Licheng Technology Co., Ltd
