Abstract: The mesoscopic structure model of three-dimensional sandwich composites was established by using finite element software ANSYS. Using this model, the stress and strain distribution of materials, fibers and resins under low-velocity impact load are studied, and the influence of resin type on the low-velocity impact resistance of the material is analyzed. Results indicated that under the low-velocity impact load, from the macroscopic point of view, the stress at the impact point and the center of the core arc is greater, and it is most vulnerable to damage, while the stress at the edge of the lower panel is minimal, and not easy to be damaged; from the meso point of view, the fiber is the main body of the bearing, and the resin plays a secondary role; the low-velocity impact resistance of epoxy resin matrix composites is better than that of unsaturated resin matrix composites.

Key words: three-dimensional sandwich composites; finite element; low-velocity impact