Abstract: As the most important process equipment in the production of composite structural parts, the mold directly determines the forming quality and precision of composite structural parts. In this paper, a slender hollow, variable section and closed composite structure is introduced. The feasibility of combined metal mould and water-soluble sand core mold is analyzed; the design idea of foam filled compound rubber core mold is put forward. The development of the product is successfully realized by the way of combined female mold and pressurization through internal inflation. It is found that polyurethane foam has a certain degree of strength and rigidity after foaming molding, and can be used to make carbon fiber prepreg laying die. At the same time, it has good swelling property for ethyl acetate, and can be used to complete the product demoulding. The rubber air bag made of vulcanized rubber has strong pressure resistance and temperature resistance, and can be widely used in the molding process of hollow closed composite structural parts.

Key words: mould, foam filling, rubber core mold, compression molding, compound material