Vertical compression performance of fiber-reinforced polymer (FRP) foam sandwich composites in hygrothermal environment

The safety of utilizing composites has garnered significant attention due to their widespread application in civil engineering, aerospace, and other fields. In the present investigation, fiber-reinforced foam sandwich composites were fabricated using the vacuum-assisted resin injection (VARI) process. The constant temperature and humidity test chamber is used to carry out damp-heat aging experiments on the specimen, and the mechanical properties after damp-heat aging are studied. The present study aims to examine the vertical compression characteristics of fiber-reinforced foam sandwich composites under the influence of hygrothermal aging. This paper also elucidates the mechanism by which the hygrothermal environment affects these composites. The results indicate that the mechanical properties of the specimens decrease after damp-heat aging. The unidirectional stacked fibers exhibit better resistance to the damp-heat environment compared to the orthogonal stacked fibers. Additionally, the inclusion of drainage holes in the setup can enhance the resistance of the specimens to the damp-heat environment.