Experimental Investigation on Mechanical Property of Hybrid Steel-to-Lattice Joint With Pyramidal Carbon Fiber Truss

As a novel type of composite sandwich structure in recent years lattice structure with carbon fiber pyramidal truss core is applied to warship’s superstructure because of its high specific stiffness and specific strength, but it is difficult to design joint between superstructure and hull and there are few researches about the mechanical property of hybrid steel-to-lattice joint. Two kinds of hybrid joint specimens are designed and their compressive and flexural properties are investigated. The experimental results show that in compression test lattice sandwich is weakest and that debonding resulted from core macro-shear and face sheet wrinkling can lead to overall instability; bearing reaction can result in resin base fracture in lattice core and face sheet delamination is the main damage mode of joint structure in three-point bending test, which happens where stiffness mutation appears.