What Are The Characteristics of RTM Process?

 

From the principle and process of RTM process, we can know that RTM process has the following main characteristics.

 

(1) RTM process is divided into two steps: reinforcement material preform processing and resin injection curing. These two steps can be carried out separately, with high flexibility and combination, and can realize “material design”.

 

(2) RTM is a closed mold molding process. The impregnation of reinforcement material and resin is completed by the rapid flow of pressurized resin in a closed mold cavity, rather than manual impregnation in hand lay-up and injection processes, and expensive mechanized impregnation in prepreg process and SMC process. It is a low-cost, high-quality semi-mechanized fiber/resin impregnation method.

 

(3) RTM process adopts reinforcement material preforming technology with a shape similar to that of the product. Once the fiber/resin impregnation is completed, it can be cured. Therefore, low-viscosity fast-curing resin can be used, and the mold can be heated to further improve production efficiency and product quality.

 

(4) The preform of the reinforcement material can be chopped strand mat, continuous fiber mat, fiber cloth, wrinkle-free fabric, three-dimensional knitted fabric and three-dimensional braided fabric, and can be selectively reinforced, locally reinforced, mixed reinforced, and pre-embedded and sandwich structures according to performance requirements, which can give full play to the designability of composite material performance.

 

(5) The closed mold resin injection method of the RTM process can greatly reduce the toxicity of harmful components of the resin to the human body and the environment, and meet the increasingly stringent restrictions on the volatile concentration of harmful gases such as styrene in advanced industrial countries.

 

(6) RTM generally adopts low-pressure injection technology (injection pressure <0.4MPa), which is conducive to the preparation of large-size, complex-shaped, and smooth-bodied overall structures.

The mold can choose different materials according to the requirements of the production scale to minimize costs.