| Carbon fiber reinforced epoxy resin matrix composites have good performance in specific strength, elastic modulus, corrosion resistance, dimension stability, fatigue resistance, and molding, therefore, they have been widely used in the field of aerospace. Nowadays autoclave-overlay technology is the main molding method to fabricate composite components applied in aerospace. However, the application of this technology in the integrated molding process of large and complex cylinder is lack of study in this paper integrated molding operation of carbon fiber reinforced epoxy resin matrix composite is studied.The cabin made of carbon fiber refined epoxy resin matrix composite is consisted of carbon fiber reinforcement and resin matrix. In this paper, according to the selection principle and the demand of use, carbon fiber of T700 12K and carbon fiber cloth of T300 1K were employed as reinforcement, and 616 and AG-80 epoxy resin were selected as matrix materials. The integrated molding processes of carbon fiber reinforced polymer matrix composites include cabin resin system preparation process, carbon fiber prepreg technology, cabin overlay technology, integrated molding technology, curing process, etc. This paper focuses on the research of the selection of resin system, curing system and the overlaying direction.The modifying effects of PEK-C, a thermoplastic resin, on the 616 and AG-80 epoxy resin system were studied by the preparation of the epoxy resin matrix using injection method and its properties were analyzed. The results show that the modified resin system has excellent heat resistance, good mechanical properties, and it can be used as matrix resin for the production of high-performance composite cabin.The curing system for the composite was obtained from the extrapolation of T-βdiagram of resin and the principle of curing kinetics. According to national standards, the samples used for property testing were fabricated by the selected curing system. The mechanical properties of the cabin were both tested by experiments and calculated through typical laminated plate theory. The comparison results indicate that the laminated plate theory can well forecast the mechanical properties of the cabin and can provide guidance to the design of the integrated molding process of the cabin.Silicone rubber thermal expansion material possesses an excellent thermal expansion property. It can supply enough pressure for the inner contour and corners of the cabin to form during the curing process, and make its final dimension satisfy the demand of utilization. In this paper, through the derivation of the linear and cubic expansion coefficients, the relationship between the dimension of the silicone rubber when heating, and the cabin pressure and temperature were achieved. This result provides good reference to the use of silicone rubber on the curing of the overall cabin.The molding process was designed according to the structural features of the overall cabin. First the cabin was divided into six parts including skin, large end frame, small end frame, vertical stiffener, circular stiffener and window. The skin, consisted of outer skin and inner skin, was molded with prepreg of unidirectional carbon fiber by two passes. The other four parts were formed respectively with prepreg of carbon fiber cloth in special molding dies. Then each part was assembled integrally in dies and pasted silicone rubber. After vacuum bag was made, according the selected curing system, the cabin was cursed in the vacuum autoclave under certain temperature and pressure.
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