关键词: 复层结构, 变形, 复合工艺, 二次胶接, 共胶接, 预变形

Abstract: Resin matrix composites possess the advantages of high specific strength, high specific modulus, high designability, strong corrosion resistance and integration molding, which have been widely used in the fields of aerospace, vehicles, ships, electronics, etc. In some practical application fields, different resin matrix composites need to be compound to obtain functional composites with excellent comprehensive properties that single resin matrix composites don′t possess. When different kinds of resin matrix composites are combined, their respective degree of size change with the change of temperature is different during the compound thermal process because of the difference of their thermal expansion coefficient, which creates the internal stress of the compound structure and eventually lead to a certain deformation. In this paper, the influence of compound process (compound temperature and compound pressure), compound methods (secondary bonding and co-bonding), the pre-deformation of aramid fiber composite on the deformation of the composite of aramid fiber/carbon fiber compound structure were studied. The results show that the deformation of the compound structure can be decreased obviously with the decrease of compound temperature. When the compound temperature drops from 180 ℃ to 120 ℃, the deformation of the compound structure decreases by 80%. Appropriate increase of compound pressure contributes to decrease the deformation of the compound structure, whereas the deformation is no longer decreased when compound pressure reaches 0.3 MPa. Aramid fiber-carbon fiber secondary bonding (aramid fiber composite and carbon fiber composite both have been cured completely before they are combined) and carbon fiber-aramid fiber dry-wet co-bonding (carbon fiber composite have been cured completely, while aramid fiber is not cured before they are combined) are beneficial to decrease the deformation of compound structure compared by aramid fiber-carbon fiber dry-wet co-bonding (aramid fiber composite have been cured completely, while carbon fiber is not cured before they are combined). The pre-deformation of aramid fiber composite is an effective way of the deformation control of compound structure.

Key words: compound structure, deformation, compound process, secondary bonding, co-bonding, pre-deformation