Flexural properties of lightweight carbon fiber/epoxy resin composite sandwiches with different fiber directions

The unidirectional CFRP laminates were prepared using the carbon fiber prepreg (CF, ZFS Materials Co., Ltd) by hot-pressing method. he lightweight pumice/Mg core was fabricated by pressure-infiltration method. In short, the selected pumice particles with the size of 3–4 mm were transferred into a cylindrical mould. Then, the molten magnesium was infiltrated into the gaps between pumice particles under vertical pressure. After solidification, the pumice/Mg core was processed to the required size for subsequent experiments.The length, width and thickness of the core material are 60 mm, 15 mm and 10 mm, respectively. The lightweight pumice/Mg core is between two thin CFRP skins, and the core material and CFRP skins are tightly bonded by epoxy adhesive under low pressure. After 24 h of curing, the composite sandwiches for the test were obtained. Three types of composite sandwiches with pumice/Mg core were obtained by using the CFRP skins with different fiber directions.