Spacecraft shell material as well as RTM (Resin Transfer Molding) molding technology and injection molding system thereof

Abstract

The invention discloses a spacecraft shell material which mainly consists of an inner composite material and an outer composite material, wherein the inner composite material takes an epoxy resin and aromatic amine curing agent system as matrix; the outer composite material takes benzoxazine resin as matrix; the transition between the inner and outer composite materials is realized through a polysulfone membrane; and the shell material is prepared by carrying out simultaneous injection and synchronous curing through an RTM (Resin Transfer Molding) technology: an injection molding system is prepared, then an overlapped fiber pre-molding body is prepared, preheating is carried out on the resin in two injection systems, and simultaneous injection, synchronous curing, demolding and finishing are carried out to obtain the spacecraft shell material. The injection molding system comprises a die, a first injection system, a second injection system, a first vacuum pumping system and a second vacuum pumping system; and a polysulfone membrane is arranged in a die cavity to divide the die cavity into an inner die cavity and an outer die cavity. The spacecraft shell material has the advantages of few technology steps, low equipment investment, low cost, high efficiency, benefit to integral molding and the like.

Description

technical field [0001] The invention relates to a fiber-reinforced composite material and its molding preparation process, in particular to a composite material with a multifunctional layer and its RTM molding process. Background technique [0002] Low-pressure liquid molding technology (Liquid Composite Molding, referred to as LCM) is a molding process widely used in the preparation of large-scale composite components, which refers to injecting liquid polymer into a closed cavity with fiber preforms, or heating and melting The resin film pre-placed in the mold cavity, the liquid polymer completes the infiltration of the resin / fiber while flowing and filling the mold, and is cured and formed into a type of preparation technology. Resin transfer molding (Resin Transfer Molding, hereinafter referred to as RTM) and resin film infiltration (Resin Film Infusion, hereinafter referred to as RFI) are the most common advanced LCM technology. LCM process technology can impregnate and...

AI Technical Summary

Problems solved by technology

For ablation-resistant composite materials, the matrix resin has an important influence on the performance of the composite material, and the most important characteristic is the carbonization characteristics, that is, the carbonization rate and the firmness of the carbonized layer. In known different types of resins Among them, the carbonization rate of phenolic resin is the highest; however, the traditional phenolic resin is more brittle, and because its curing reaction is a polycondensation reaction, the reaction releases a large amount of water and small molecules, which will cause the porosity of the composite product to be relatively large. , can no longer meet the higher requirements, which has become a bottleneck restricting its application in the preparation of resin-based ablation-resistant components by RTM

[0005] In addition, the traditional RTM process can only inject a single resin. For the above-mentioned spacecraft shell composite components with multi-functional layers, the usual preparation method is to use the RTM process to prepare each functional layer separately, and then bond them together , which not only increases the difficulty and complexity of the process, but also reduces the reliability of the overall structure

If simultaneous injection is used to prepare such composite components at one time, firstly, because the injection process characteristics and curing process characteristics of different types of resins are very different, it is difficult to achieve simultaneous injection and simultaneous curing of two different types of resins; secondly, due to the The two resins enter the mold cavity at the same time, there is no isolation layer between the reinforcements of different functional layers, and the two different types of resin glue will produce mixed flow

It can be seen that the existing RTM molding technology has not been able to effectively solve the one-time integral molding of this type of composite material component with multi-functional layers.

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