Method used for preparing liquid state moulded composite material sandwich structure from foam filled honeycomb

Abstract

The invention belongs to the technical field of composite material preparation, and relates to a method used for preparing a liquid state moulded composite material sandwich structure from foam filledhoneycomb. The method is used for solving difficulties in liquid state moulding and honeycomb using. According to the method, a phenolic foaming material with both material and technology matching performance with the honeycomb material and the liquid state moulding material is adopted for pre-filling of honeycomb holes, and then after pre-curing, the foamed filled honeycomb core material is adopted in liquid state moulding so as to obtain the foam filled honeycomb sandwich composite material using liquid moulding technology. The method is adopted to prepare that foam filled honeycomb sandwich structure, so that a problem that it is difficult to introduce honeycomb into liquid state moulding is solved, manufacturing difficult problems are solved, the honeycomb core material is suitable for a plurality of liquid state moulding, and the adaptability is relatively high.

Description

technical field [0001] The invention belongs to the technical field of composite material preparation, and relates to a method for preparing a liquid molding composite material by filling honeycomb with foam. Background technique [0002] The honeycomb sandwich structure is widely used in the structure of aerospace vehicles due to its light weight and high rigidity. At present, the honeycomb sandwich composite material is mainly manufactured by the autoclave forming process, but the manufacturing flexibility of the autoclave forming process is limited. For some A structure with a complex shape cannot be applied, and the manufacturing cost is relatively high. In recent years, low-cost liquid composite molding (Liquid Composite Molding, LCM), represented by resin transfer molding (Resin Transfer Molding, RTM) and vacuum assisted resin infusion molding (Vacuum Assisted Resin Infusion, VARI), etc. It has gradually become an important means of manufacturing integrated and comple...

AI Technical Summary

Problems solved by technology

However, for liquid forming composite materials, the currently commonly used honeycomb core materials cannot achieve process compatibility

This is due to the fact that there is a large area of ​​low-viscosity resin flowing during the liquid molding process, and the resin easily enters the cellular structure of the honeycomb, resulting in a substantial increase in the weight of the composite material structure, which seriously affects its weight reduction effect

[0003] In order to use the honeycomb core material in the liquid forming process, relevant research work has been carried out at home and abroad. For example, EP0722825A2 uses adhesive film, prepreg, and dry fabric as a combination for the RTM process, and can prepare the corresponding honeycomb sandwich structure. However, this process must use an adhesive film, resulting in an increase in the weight of the composite sandwich structure, and this packaging method uses an uncured adhesive film, and the low-viscosity resin may flow into the honeycomb grid under higher injection pressure during the subsequent RTM process Internal situation; US20030082339 improved the honeycomb packaging method of EP0722825A2. First, the honeycomb was sealed and cured with an adhesive film, and then the RTM process was performed. This method also used an adhesive film, which increased the weight of the part, and was divided into two steps Although the technology increases the cost of the process, it reduces the risk of RTM resin entering the honeycomb cells; CN201310717193 uses prepregs to seal the honeycomb, and completes the precuring or curing of the prepregs in an autoclave, and then uses The liquid molding process prepares honeycomb sandwich composite materials. The matrix resin of the prepreg used in this process needs to be compatible with the liquid molding resin injected later, which limits the selection of prepreg materials to a certain extent, and the honeycomb packaging When curing, it is necessary to use an autoclave for preforming, which increases the process cost